I CLASSIFICATION CHANGED TO 

IFIED 

By Authority of 

By/hiM/7'Z— Date (o41,0 '70 

CHANGE ALL MARKINGS 

PRIOR TO CIRCULATION 

NRO APPROVED FOR 

RELEAS1 JULY 2015 r 

AEROSPACE 

LIBRARY 

Document No. RCopy No. 

• 

AEROSPACE CORPORATION 

PRr': -1RTY OF 

RE7L; ;C'RPORATTok- 

'-) U3RARy 

UNCLASSIFIED 
0 0 LL N 

0 

0_ 01 

0_ (0 

¢ w 

CC 

Z 
RO APPROVED FOR 

ELEASE 1 JULY 2015 

istr u ctions: 

UNCLASSIFIED 

11111111101DOCUMENT CHANGE RECORD 

behind the cover, or behind the title page if there is 1) This form will be inserted into a Secret document immediately 

no cover, whenever any addition or change is made. 

2) Record all additions or changes inserted into or attached to a document and the 

solete by such additions or changes. 

Title of Basic DocumentO)An analysis of the requirements for very high accuracy image motion 

EROSPAC E FORM 3388 

compensation. TOR-669(6107-40)-1. 

Classified Document Control No. (CDCN)- AS-65-0000-03578; c.32 

INCORPORATED MATERIAL 

disposition of all pages made obCDCN & Copy No. of 

Incorporated Contents 

Classification 

Down- Grade 

Group 

Orig. 

Date 

Disposition of Remainder of Incorporated document (v) 

Disposition of 

Replaced Pages (v) Change made 

by (name) 

Date of 

Change 

None Retained 

Destroy.

None Rerained 

Destroy 

AS-65-0090-04815, c.32 

C&=AAcc -dact,ti-d 

S 4 11-4-65 XX " X AOLIB/h . 12-10-65 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

;',7NIOU 

.rail 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

AS-65-0000-03578 

(for security control only) 

Report No. TOR-669(6107-40)-1 

(U) AN ANALYSIS OF THE REQUIREMENTS FOR 

VERY HIGH ACCURACY 

IMAGE MOTION COMPENSATION 

Prepared by 

R. Grove, A. Mandl, and L. E. Watson 

Optical and Electrical Department 

El Segundo Technical Operations 

AEROSPACE CORPORATION 

El Segundo, California 

Contract No. AF 04(695)-669 

October 1965 

Prepared for 

COMMANDER SPACE SYSTEMS DIVISION 

AIR FORCE SYSTEMS COMMAND 

LOS ANGELES AIR FORCE STATION 

Los Angeles, California 

GROUP- 4 

Downgraded at 3-year intervals; 

UNCLASSIFIED declassified after 12 years. 

AMR 

This document contains information affecting the notional defense of the United States within the meaning of the Espionage Laws, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by low. 

• 
W„,11,AA5 )2IA,r,,t_ 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLAs5irICu 

NNW 

Report No. 

TOR-669(6107-40)-1 

(U) AN ANALYSIS OF THE REQUIREMENTS FOR 

VERY HIGH ACCURACY IMAGE MOTION COMPENSATION 

Prepared 

R. Grove A. Mandl L. E. Watson 

Approved 

A. G Nash, Head . W. Nordyke, Director 

Optical and Electrical Department MOL Experiments Development 

Sensing and Information Subdivision Manned Systems Division 

Electronics Division 

Ufa 

This document contains information affecting the national defense of the United Stoles within the mooning of the Espionage Lows, Title 

IS, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to CM unauthorized person is prohibited by low. 
NRO APPROVED FOR 

SSLFIED 

RELEASE .1 JULY 2015 

- CONTENTS 

1. 0 INTRODUCTION 1 - 1 

2. 0 IMAGE MOTION ANALYSIS 1-2 

2. 1 Vertical Photography 1-3 

2. 2 Side-Oblique Photography 1-4 

2. 3 Forward and Forward plus 

Side-Oblique Photography 1-7 

APPENDIX A. Image Motion Considerations for Vertical and 

Side-Oblique Photography A- 1 

APPENDIX B. Analysis of Image Motions in a Camera having 

Forward and Side Orientations B-1 

APPENDIX C. Some Error Analyses and Design Details for the 

• 

Forward and Side-Oblique Strip Camera C- 1 

APPENDIX D. Preliminary Design Consideration on a 

High Accuracy Film Drive Mechanism D- 1 

UNCLASSARED =MN 

This document contains information offecting the national defense of the United Stoles within the meaning of the Espionage Laws, Title 

18, U.S.C., Section 793 and 794, she transmission or revelation of which in any manner to on unauthorized person is prohibited by low. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

tailifirD 

FIGURES 

1. Image Motion: Vertical Photograph 1-4 

2. Image Motion: Side Oblique 1- 5 

3, Resultant Image Velocity Vectors 1-5 

4. Image Motion due to Forward, Backward or 

Forward, or Backward Plus Side-Oblique 1-8 

UNCLASSIFIED 

alga 

This document contains information affecting the notionol defense of the United States within the mooning of the Espionage Lows, Title 

IS, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to an unouthorized person is prohibited by law. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

*WAD 

1,0 INTRODUCTION 

At the request of the MOL Experiments Development Office, a design and 

error analysis was initiated to determine the requirements and feasibility 

of a camera system capable of image motion compensation over the entire 

image plane to an accuracy of at least 0. 1% of the forward velocity component 

of the vehicle at the image plane. In order to complete such a study it was 

necessary to perform a detailed analysis of the image motion sources and the 

associated compensation error tolerances, to investigate in concept various 

feasible mechanical designs of the camera image motion compensating (IMC) 

mechanisms, and to perform a detailed analysis of the IMC servo control 

system design requirements and feasibility based upon the above analysis. 

A basic premise of this study was that the image velocity sensing would be 

done by a man aided tracking system that has the capability to determine the 

image velocity direction and magnitude to a resultant accuracy far in excess 

of the required system accuracy of 0. 1%. It was assumed that in general the 

tracking system would be basically as described by the IBM Image Velocity 

Sensor Subsystem (IVSS) Study Reports (SSD-TR-64-277). 

Characteristically, this system employs a variable power, servo controlled, 

direct viewing, pointing and tracking telescope. The servo controlled tracking 

elements are used in conjunction with a general purpose computer. Initial 

tracking rates would be calculated for a given target to appear in the field of 

view at some azimuth within the limits of the operating system. Automatic 

tracking would begin at acquisition, and rate corrections would be provided 

as indicated from manual corrections made by an operator viewing the target 

and keeping it at a prescribed point in the optical field of view. Accurate data 

would be provided by the computer regarding the angles and angular velocity 

of the target line of sight with respect to the spacecraft. Angular rate data 

would be used to precisely control the synchronized motion of the recording 

film at the optimum or other prescribed time of photography. 

• UNCIASSIFIED 

111.11111111 

This document contains information affecting the national defense of the United States within the meaning of the Espionage Laws, Title 

IS. U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• Since this system in actuality employs an open loop operation, it is mandatory 

that a careful analysis of the design and tolerances of the tracking and camera 

systems be made so that the required tolerances involved in translating the 

computed image velocity resulting from the man aided IVSS tracking into precise film drive and other complex motions be understood. 

This study is a result of the combined efforts of personnel of the Optical and 

Electrical Department of the S & I Systems Subdivision and of the Controls 

Department of the G & C Subdivision. Robert Grove and Lloyd Watson were 

responsible for the image motion analysis, Al Mandl for the mechanical 

design considerations, and Darrel Gieseking for the servo systems analysis. 

Lloyd Watson was also responsible for the coordination of these studies. 

The details of the image motion analysis are contained in Appendixes A, B, 

and C. Appendix D sets forth the mechanical design considerations and the 

development of a recommended design approach. The details of the IMC 

servo control system requirements and design study have been issued as a 

separate report by the Controls Department. 

2. 0. IMAGE MOTION ANALYSIS 

Image motions at the image plane of aerial cameras result from the apparent 

ground motion due to the forward motion of the vehicle, camera and vehicle 

angular motions, vibrations and atmospheric disturbances. In this study the 

atmospheric effects are not considered. The magnitude and direction of the 

image motion depend upon directions of camera pointing as well as upon the 

vehicle velocity and altitude and are a function of the lens focal length. 

Basically, for vertical photography, the image velocity, Vio, is given as 

V. = V 

H F (1) 

UNCLA$S1F1ED 

This document contains information affecting the notional defense of the United Stoles within the meoning of the Espionage Lows, Title 

IS, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by low. 
UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

where 

V = vehicle velocity 

H = altitude 

F = lens focal length 

V. is opposite in direction to the line of flight. However, since the image 

motion direction is a function of camera pointing or the optical line-of-sight 

direction, there will be resultant image motion components which are not 

parallel to the line of flight and may not be in the same direction. These 

motions have been analyzed as functions of camera pointing angles and the 

resultant position in the camera focal plane. 

Four modes of camera operation are considered. Each gives rise to a unique 

situation relative to image motion compensation; The modes are 

• 

1. Vertical photography 

2. Side-oblique photography 

3. Forward or backward-oblique photography 

4. Forward or backward-oblique plus side-oblique photography. 

2. 1 VERTICAL PHOTOGRAPHY (Appendix A) 

As detailed in Appendix A, the image velocity, resulting from strictly vertical 

photography, is a function of V/H and lens focal length (Equation 1). Each 

image motion point in the image plane moves in one direction only and all the 

resultant motions across the image format are parallel to each other. The 

direction of the motion is opposite to the forward direction of the camera 

vehicle. This is shown schematically in Figure 1. 

Thus if the film is parallel to and in synchronism with this motion, perfect 

IMC can be accomplished. The precision of the film drive, the ability to 

sense and determine the image motion (V/H sensing), and to synchronize the 

film speed to the image velocity are the critical parameters. Cameras which 

operate in this fashion and employ a narrow slit across the center of the image 

UNCLA$S1FIE 

This document contains information affecting the national defense of the United Stoles within the meaning of the Espionage laws, Title 

18, U.S.C., Section 793 and 794, the ttonwnission or tevelotion of which in any manner to on unauthorized person is prohibited by tow. 
UNCLAS IFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

Figure 1. Image Motion: Vertical Photography 

plane to control exposure are in common use. For this simple case, limited 

by the film drive mechanism alone, precisions approaching 0. 1% are rarely 

achieved at present even in the laboratory. 

Z. 2 SIDE-OBLIQUE PHOTOGRAPHY 

Since it is not always possible to pass directly over an area of interest so 

that vertical photography can be accomplished, it generally is necessary to 

provide a means for accomplishing side-oblique photography. Also from 

Appendix A, it was shown that the resultant image motion, Vis, is given by 

V 

V. = —H— F(cos + sin tan pe) ( 2) 

where 

Vo 

is the apparent ground velocity 

0 is the obliquity or roll angle (from the local vertical to the 

center of the optical axis) 

Ae is the angle of a point off axis. 

Since A0 can be positive or negative with respect to 0, it is readily apparent 

that, although the resultant image motion vectors are parallel to each other, 

they differ in magnitude, increasing from the corresponding greater distance 

edge of the image to the lesser. • 

UNCLASSiFIED 

This document contains information alfecling the national defense of the United States within the meaning of the Espionage Laws, Title 

IB. U.S.C., Section 793 and 794, the tronsmission or revelation of which in any manner to on unauthorized person is prohibited by taw. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLASSIFIED 

Figure 2. Image Motion: Side Oblique 

Therefore, no single film velocity can compensate for the motion across the 

film width. If the film is driven at a speed corresponding to that at the 

center, on the optical axis, then resultant image motion vectors will be as 

indicated by Figure 3. 

Figure 3. Resultant Image Velocity Vectors 

However, by rotating the film platen (image plane) while the film is being 

driven at the IMC speed, the resultant velocities can be reduced to zero. 

The required rotational rate, (1.) of the platen, is also a function of the V/H 

as well as the obliquity angle and must correspond to 

V 

o 

ca

p 

= —H sin (3) 

UNCLASSIFIED 

=Ma 

This document contains information affecting the notional defense of the United States within the meaning of the Espionage Laws, Title 

Ifl, U.S.C., Section 797 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by low. 
UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

However, as noted in Appendix A, it is now necessary to translate the image 

plane laterally in a direction parallel to the initial slit orientation. This is 

required because, as the image plane (film platen) is rotated, the film is no 

longer being driven in a direction parallel to the motion at the optical center, 

thus a cross track error is introduced. The required compensating translational motion, Vt, will be 

Vt 2 H = TFM2sin 20 (4) 

All three motions will be required if a system accuracy approaching 0. 1% is 

achieved. Since other system errors will likely occur, such as in pointing, 

optical alignment, motion sensing, vibration, etc. , the required precision of 

the IMC due to the servo controlled mechanical drive systems should be somewhat better than the required 0. 1%. Where three simultaneous motions are 

required it was decided that each should not contribute more than half of the 

above tolerance or be in error more than 0. 0005 Vo

. Combined in an RMS 

fashion this would allow a net average error attributable to the servo controlled drive systems of approximately 0. 0008 Vo. 

The maximum allowable error for each of the separate drive motions, so 

that the 0. 0005 V

o 

tolerance will not be exceeded, will be 

Film drive error: e

f 0. 0005 V0 ( 5) 

or 0. 05% 

Rotational drive error: e

r 

= 0. 0005 F 

d tan 0 

(6) 

where d is the distance along the slit from the optical center. 

UNCLASVFIED 

This document contains information affecting the national defense of the United Stales within the meaning of the Espionage Laws, Title 

IS. U.S.C.. Section 793 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by law. 
NRO APPROVED FOR UN 

RELEASE 1 JULY 2015 

• 

Assuming that the most stringent case would be at a side-obliquity angle, e , 

of about 45 degrees and a total exposing time (frame time) of 5 seconds then 

e r= 0. 035 or a rotational drive error of ±3. 5% could be tolerated. 

Translational drive error: e _ Vo _ 0. 0005 

t Vt t —V sin 0 

( 7) 

Assuming the same conditions as for (6), the translational drive accuracy 

could be ±0. 2%. 

2. 3 FORWARD AND FORWARD PLUS SIDE - OBLIQUE 

PHOTOGRAPHY (Appendix B) 

It is possible to obtain stereo photography using only one camera and lens 

system providing that the pictures of the object space can be obtained from 

two different viewing angles or optical lines of sight commonly referred to 

as the stereo angle. The stereo angle is not critical and can vary from 2 or 

3 degrees to many degrees but with some variation in the apparent stereo 

effect to be expected. 

If stereo photography is desired from a satellite vehicle having only one 

camera system, then it becomes necessary to point the optical axis forward 

and backward, or forward plus side-oblique and backward plus side-oblique in 

order to obtain the stereo pairs. In doing so, the image motion components are 

not readily apparent and the image motion compensation might be complex. 

These modes of operation generally would be considered only if stereo 

photography were a requirement. 

As noted in Appendix B, the image velocities resulting from forward or 

backward-oblique photography vary nonlinearly across the image plane. With 

reference to a vanishing point located on the horizon which is the intersection 

of the the horizon line and the flight line, the image velocities will be as 

shown in Figure 4. 

This document contains information offecting the notional defense of the United Stoles within the meaning of the Espionage Lows, Title 

i A, U.S.C., Section 793 and 794, the transmission or I avelotion of which in any manner to on unauthorized person is prohibited by tow. 
11111IMIIMINIM 

-•-111.- 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

Figure 4. Image Motion Due to Forward, Backward 

or Forward, or Backward Plus Side-Oblique 

Considering a slit across the film it is noted that the image velocities perpendicular to the slit are constant and can be removed by the proper film 

speed. The resultant image velocities along the slit are linear with position 

and therefore can be removed by a motion that changes the image size by a 

prescribed rate. The most likely way to accomplish this would be by a controlled zoom (Appendix D). Forward or backward-oblique plus side-oblique 

photography result in the same situation as the above, hence the corrections 

are made in the same way. It should be noted that in compensating for this 

cross track motion component by "zooming" changes the image velocity along 

the optical axis, because of the increase or decrease in the lens focal length. 

Hence the film drive must be continuously variable over this range. 

The total image motion, Vio, at the image plane in this mode is given by 

V. = Fv 

cos

2

p cos 

V exp(- sin p cos et) (8) 

• 

UNCLASSIFIED 

This document contains informotion affecting the notional defense of the United Stales within the meaning of the Espionage Lows, Title 

113, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by low. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

where 

p is the pitch angle 

0 is the roll angle 

t is the time duration of photography 

The image motion component (V;0) perpendicular to the slit corresponding to 

the film drive rate is 

V.' .= F —V 

cos

2

p cos 0 H (9) 

and must be accurate to about 0. 05 to 0. 06% if the desired IMC is achieved. 

The image motion component, Vi'o , along the slit is 

Vio = exp(2 —Vd sin p cos p cos 0) (10) 

where d is the distance measured along the slit from the optical center. 

If the maximum error allowable for this component is also 0. 0005 V. the 

fractional error of the zoom drive is given by 

AF 1 = 0. 001 

 F 

tan p d 

For the most severe case of 30 deg forward oblique, and for a format 

dimension (d) of 1 foot and a focal length of 20 feet, the zoom drive accuracy 

is found to be 3-1/2%. 

This document contains information effecting the notional defense of the United Stoles within the meaning of the Espionage Lows, Title 

18, U.S.C., Section 793 and 794. the t,onicnission or revelation of which in ony manner to on unauthorized person is prohibited by 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLASSIFIED 

• APPENDIX A 

(A-1) V V. = - F H 

IMAGE MOTION CONSIDERATIONS FOR VERTICAL 

AND SIDE-OBLIQUE PHOTOGRAPHY 

1. 0 VERTICAL PHOTOGRAPHY 

The relationships of image motion with altitude and vehicle velocity are well 

known in aerial photography. As can be seen from Figure A-1, the image 

velocity, Vio, at the optical center is 

where 

V = apparent ground velocity 

H = altitude 

F = lens focal length 

Figure A-1. Geometric Relationship Between Ground Motion 

and Image Motion for Vertical Photography 

UNCLASSIFIED 

This document contains information affecting the notional defense of the United States within the meaning of the Espionage Lows, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized Person is prohibited by law. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

equiNICLATal& ni

• 

Also, considering an object point off the optical axis by an angle then the 

image motion corresponding to that point in the image plane will be 

V.' = (A-2) 

Since 

- F C or F sec ri 

OS Y1 

(A-3) 

and 

=cos 

 or H sec ri 

(A-4) 

substituting in Equation (A-2) results in 

V V. = - —F H

(A-5) 

Thus, the image motion across the field of view for vertical photography is 

the same as at the optical axis. 

2. 0 SIDE-OBLIQUE PHOTOGRAPHY 

The image motion relationships for side-oblique photography can best be seen 

by referring to Figure A-2. In this figure, H is the altitude and M the slant 

range to the center of the field of view along the optical axis. 8 is the 

obliquity angle or the roll angle. A0 is an off-axis angle. 

Since M = H sec 0, the image velocity at the optical center is 

V FV 

V• F H sec - —11- 1 cos 0 (A-6) 

This document Contains information affecting the nations"! defense of the United States within the meaning of the Espionage Lows, Title 

18, U.S.C., Section 793 end 704, the transmission or revelation of which In any manner to on unauthorised person is prohibited by low. 
Vo

F sec AO 

H 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

Figure A-Z. Geometric Relationship Between Ground Motion 

and Image Motion for Side-Oblique Photography 

Considering an object off axis by an amount p0, then 

VipO - H sec(0 + ,6,0) 

(A-7) 

VoF 

(cos 0 - sin e tan AO) 

The velocity increment along a slit perpendicular to the direction of motion, 

measured from the optical axis, is the difference of equations (A-7) and 

(A-6) or 

VoF VF 

Vi p0 - V

io H = (cos 0

o sin 9 tan AB) cos 

. 

V

o

F 

(sin 0 tan A0) 

UNCLASSIFIED 

(A-8) 

This document contains information affecting the national defense of the United Slates within the meaning of the Espionage lows, Title 

113, U,S.C., Section 793 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by low. 
= H 

V 

sin 0 (A-12) 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

It should be noted that in reference to the motion at the optical center, this 

may be greater or smaller than Vic)depending upon whether Pe is positive 

or negative. Thus the image motion, although parallel, is varied continuously 

in magnitude from the nearest to the farthest point across the field. 

If the film plane (or platen) is rotated about the optical axis during the exposing interval with an angular velocity, w , when the slit is perpendicular 

to the flight line, there will be a velocity increment given to the film which 

is do.), where d is the distance from the optical axis measured along the slit. 

Then 

pV = dw (A-9) 

But 

d = F tan pe (A-10) 

Substituting (A- 9) and (A-10) into (A-8) for ViAe - Viogives 

VF 

1Th.) tan AO - o (sin 8 tan pe) (A- 11) 

Thus it is seen that the compensation is exact and independent of the angular 

field of the optical system when the platen is in this orientation. The required 

angular velocity is 

Although this rotational motion can completely compensate for the nonuniform motion resulting from side-oblique photography, in so doing another 

secondary motion is introduced. Assuming that the film drive is a cylindrical 

UNCLASSIFIED 

This document contains informotion affecting the notional defense of the United Stotes within the meaning of the Espionage Laws. Title 

18. U.S.C.. Section 793 and 794. the transmission Or revelotion of which in any manner to an unauthorized person is prohibited by law. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

platen, as it is rotated about the optical axis, after time, t, the drum has 

rotated an angle, a, and the direction of film drive has also changed by an 

amount a, from the desired direction, (Figure A-3) where a is given by 

a = wt (A- 13) 

and t is the total frame time. 

A 

The image motion, imparted by drum rotation, along the slit in the direction 

of A to B is then 

Vt 

= V. sin a = V. sin wt 

or 

V )2, 

v

t

- F( t sin 20 (A- 14) 

This image motion must therefore be compensated by translating the drum a 

like amount along its primary spin axis. 

Figure A-3. Vector Diagram of 

Film Image Motion 

After Drum Rotation 

We are now prepared to consider the allowed errors in each of these three 

motions of the drum; these are AV. /V.0' 1 Aw/w, and AVt

/V io t. • 

UNCLA§SIFIED 

This document contains information offecling the notionol defense of the Uniled Stoles within the meaning of the Espionoge laws, Title 

18, U.S.C., Section 793 and 794, the tionsmission or e ev clot ion of which in any manner to on unnutholiced person is prohibited by low. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

UNCLASSIFIED 

111111111PM 

Since the RSS of these errors should yield no more than 0. 001 fractional 

error in film speed, then it should be reasonable to allot 0. 0005 fractional 

error to each of these error sources. 

It is immediately apparent that the primary drum rotation error (AV. /V. ) 

must not exceed 0. 0005. The other errors are more subtle. An error in the 

secondary angular rotation rate of the drum (Aw) will cause an error in film 

speed at the edge of the format (Ad) of 

Ad = dAw (A- 15) 

Allowing 

pci = 0. 0005 V. 

and dividing (A- 15) by (A-16) yields 

(A- 16) 

• V. 

L') = 0. 0005 d10

w 

(A- 17) 

Substituting (A-6) and (A- 12) into (A- 17) yields 

= 0. 0005 d tan 0 

Assuming. F to be 20 feet, d = 0.5 foot, and 0 = 30° , then 

(A-18) 

1 = 0. 035 = 3 2

— (A- 19) 

In other words, a 3-1/2% error in the secondary rotation rate of the drum 

will yield 1/20% error in film speed at the edges of the format. 

UNC COME c I •Ne. 

This document contains information affecting the notional defense of the 1.1n ■ red Stales within the meaning of the Espionage Lows, Title 

18, U.S.C., Section 793 and 794, the itensmission or revelation of whCc-h in any manner to on unauthorized person is prohibited by law. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLASSIFIED 

• 

(A-20) 

(A-21) 

(A-22) 

The allowed error in drum translation (pVt) is assumed to be 

AVt = 0.0005 V. 

Dividing by Vt 

V. V. 

= 0. 0005 1O V

t Vt 

Substituting (A-6) and (A-14) into the right hand side of (A-21) yields 

AVt 0. 0005 

Vt 

V°/Ht sin 0 

Allowing Vo/H = 0. 04 radian/sec, 0 = 30° , and t = 5 seconds, then 

1 plIF11ED 

Vt 

AVt = 0.5 x 10-2 = 0.5% (A-23) 

In other words, a 0. 5% error in drum translation speed will yield a 0. 05% 

error in film speed. 

This document contains information affecting the notional defense of the United States within the meaning of the Espionage Laws. Title 

18, U.S.C., Section 793 and 794, the ttansmissian or revelation of which in any manner to an unauthorized person is prohibited by tow. 
= ±I5 DEG 

10 

ROLL= 0 

4 

FOCAL LENGTH= 25 FT 

3 

 V/H = 0.84 RADIANS/SEC 

IMAGE SPEED IS DIRECTLY 

PROPORTIONAL TO FOCAL 

LENGTH AND V/H RATIO 

2 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

IMAGE SPEED IN TH E CENTER OF THE FI ELD,IN. /SEC 

UNCLASSIFIED 

10 20 30 40 50 60 

PITCH, DEG 

Figure A-4. Image Speed as a Function of Pitch and Roll for Cameras 

Pointing Forward and to the Side 

UNCLASSIFIED 

11111111.111111r 

This document contains information affecting the notional defense of the United States within the meaning of the Espionage Laws, Title 

IS, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by low. 
UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

APPENDIX B 

ANALYSIS OF IMAGE MOTIONS IN A CAMERA HAVING 

FORWARD AND SIDE ORIENTATIONS 

Envision a camera system oriented as shown in Figure B- 1 with a cartesian 

coordinate system (x, y, z) whose xy plane defines the ground plane of a flat 

earth. Let the origin be fixed in the nadir point of the camera whose focal 

length is F. If the travel of the camera is "horizontal" and in the y direction 

the ground points will appear to be moving in the -y direction. Let the camera 

be at an altitude H and 1 , 1 , 1 be unit vectors along the directions of the 

x y z 

x, .y and z coordinates respectively. Let any particular ground point be 

defined by the vector G. 

Envision a second coordinate system (x" , y" , z") where 1" , 1" , 1" are 

x y z 

unit vectors along the directions of the x" , y" , and z" axes respectively. 

Let the origin be located at the camera nodal point. Let the image plane be 

a plane parallel to the x" y" plane. Let the principal ray from the ground 

point G intersect the image plane at the head of the vector. I. The tail of the 

vector I is bound in the camera nodal point. The vector KT measured from 

the ground point G to the camera nodal point also lies along the principal ray 

and, of course, has the same orientation as I but is K times longer. 

From Figure B-1 we obtain the following three equations 

+ KT = Hl

z 

T 1"x. + 

xyz 

1"y. + 1"F 

= l

x

x

g 

+ l

y

y

g 

UNCLASSIRED 

This document contains information affecting the notional defense of the United States within the meaning of the Espionage Lows, Title 

18, U.S.C., Section 793 and 794. the transmission or revelation of which in any manner to an unauthorized person is prohibited by low. 
CAMERA IMAGE PLANE 

CAMERA NODAL POINT 

GROUND PLANE 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

IFIED 

Figure B-1. Relations of Principal Vectors in the Ground and 

Camera Coordinate Systems 

UNCLASSIFIED 

11111111111111.111111 

This document contains information affecting the notional defense of the United Slates within the meaning of the Espionage Lows, Title 

18, U.S.C., Section 79J and 794, the transmission or revelation of which in any racily," to on unauthorized person is prohibited by law. 

• 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

FIED 

• 

where 

is the vector from the camera nadir point to any 

ground point on a flat earth 

y is the coordinate of the ground point in the forward 

g direction 

x is the coordinate of the ground point in the side 

g direction 

is the vector from the camera nodal point to the 

image of the ground point in the camera image plane 

xi, yi are coordinates of the image point in the image plane 

measured from the optical axis 

F is the camera focal length 

H is the camera latitude 

K is a proportionality constant 

1 , 1 , 1 are unit vectors in the ground coordinate system in 

x y z which the z direction is up, the y direction is forward, and the x direction is to the side (as defined 

for a right handed coordinate system) 

are unit vectors in the camera coordinate system in 

which the z" direction is along the optical axis, and 

the x" and y" directions are defined in the image 

plane. 

Eliminating G and T from equations (B-1), (B-2), and (B-3) yields 

1"Kx. + 1" + 1"KF = - lx - 1 y + lH 

x 1 y z x g y g z 

(B-4) 

Useful relationships between the two coordinate systems can be obtained by 

assuming that the camera is oriented vertically. In this special case 

1" = 1 

x x 

1" = 1 

Y Y 

1" = 1 

z z 

Vertically Oriented Camera 

UNCLASSIFIED 

This document contains information affecting the national defense of the United Stale, within the mooning of the Espionage taws, Title 

18, U.S.C., Section 793 and 794, the tfansmiss ■ on or revelation of which in any manner to on unauthorized person is prohibited by low. 

1" 

x y z 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLASSIFIED 

• 

Let us now pitch the camera forward by an angle p. In this special case let 

1' = 1 

x x 

1' = 1 

Y Y 

1' = 1 

z z 

Camera pitched forward only. 

Figure B-2. Relation Between Unit Vectors 

of the Camera to Intermediate 

Coordinate Systems 

(15 example let the trigonometric functions of some angle be written as 

sin cb = 

cos 0 = Co 

tan 0 = 

UNCLASSIFIED 

This document contains information affecting the notional defense of the United States within the meaning of the Espionage Lows, Title 

U.S.C., Section 793 and 794. the transmission or revelation of which in any manner to on unauthoriced person is prohibited by law. 

Then from Figure B-2 we have 

1" = 

x x 

1" = 1' cos p + 1' sin p 

Y yz 

1" = 1' sin p + 1' cos p 

z y 

1 12 

Since the equations that follow tend to become lengthy, the trigonometric 

forms are presented more compactly than is common practice. As an 

(B-5) 
UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

Using this compact form (B-5) becomes 

1" = 1' 

X x 

1" = + 

Y Y P z P 

1"=-1'S -1-1'C 

z yp z p 

Now roll the camera an angle 0. Then from Figure B-3 we have 

1

X = 1 xC0 + 1 

z

S 

1' = 1 

Y y 

1' = -1

x

S

e 

+ 1

z

C8 

(B-6) 

(B-7) 

• 

Iy, Iy 

Figure B-3. Relation Between Unit 

Vectors of the Intermediate to the Ground 

Coordinate Systems 

Substituting (B-7) into (B-6) yields 

1" = 1 c + 1 s x e z 0 

1" = - 1 s sp, +1 C +1 S Cpi 

xps, y p zp •-• 

1"=-1C,Sph -1S +1CCA 

x yp z p 

(B-8) 

• 

UNCLASSIFIED 

11111111111111111111111 

This document contains informotion affecting the notional defense of the United Stoles within the mooning of the Espionage Laws, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by low. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

UNCLASSIFIED 

A useful relationship now exists between the two coordinate systems. 

Equations (B-8) give the camera unit vectors in terms of the ground unit 

vectors. 

Substituting (B-8) into (B-4) and equating vectorial coefficients yields 

K(Coxi- Sp Soyi- Cp SoF) = -xg 

K(C 

p 

 y. - S 

p

F) = -y g 

K(Soxi+ SpCoyi+ CpCoF) = H 

Since K is a constant of little significance, it can be eliminated by first 

dividing (B-9) by (B-11) and then (B-10) by (B-11). This procedure yields 

and 

x

g _ 

Cox

1

. - S

p

Soy

1

. - C

p

SoF 

H Sox.1 + S 

pCn y. + C 

p

C F 

y C y. - S F 

g _ P 1 P 

H Se)x

. 

+ S C y. + C Cc,F p 0 p 

(B- 12) 

(B- 13) 

Equations (B-12) and (B-13) are important because they give the relationship 

between any ground point coordinates (x 

g 

 , y 

g

) and their image coordinates 

(x., y.) as a function of camera altitude, focal length, and orientation 3. 

( H , F, p, 6). 

The fundamental purpose in performing this analysis is to determine the 

image motions as a function of satellite travel, with the ultimate hope of 

finding a suitable method of image motion compensation. The next step is 

therefore to find relationships for image motion. 

UNCLA43SAFIED 

1111111111111111111111111 

This document contains information affecting the notional defense of the United States within the meaning of the Espionage Lows, Title 

18, U.S.C., Section 703 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by law. 
UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

This can best be done by differentiating (B-12.) and (B- 13) with respect to 

time and rearranging the resultant equations. The algebraic manipulations 

required are lengthy and are therefore not presented here. The procedure 

required, however, is discussed below. 

The ground coordinate system was originally defined with the y axis as the 

direction of satellite travel. Since the ground coordinate system travels 

with the satellite, all the ground points appear to be travelling in the negative 

y direction or 

dy 

= V dt 

dx 

dtg - 0 

(B-14) 

where V is satellite velocity. 

In order to keep the equations compact, the notation of a single dot is used 

above a variable to represent that-variable's derivative with respect to time, 

i.e., 

4 = 

dt 

Employing this notation modifies (B- 14) as follows 

= -V xg =0 (B-15) 

The procedure employed took the following steps: 

1. Differentiate (B- 12) and (B- 13) with respect to time. 

xi and yi are variables and F, H, p, and 0 are constants. 

This step yields two equations both containing xiand yi 

in addition to x., y., F, p, and 0. 

UNCLASSIFIED 

This document contains information affecting the notional defense of the United States within the rneoning of the Espionage Laws, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by law. 
• 

Yip 

(B-16) 

2. Substitute (B-15) into the two equations. 

3. Solve the two equations for Xi and Yi in terms of xi, 

F, p, and O. This last step yields the important 

relationships of 

1 v 

xi = F H spxi(Sexi+ SpCoyi+ CpCoF) 

Y. = F H —V(S pi y + C 

p 

 F)(S0 x. +SpCO 

 yi +C 

po 

C,F) (B-17) 

and 

UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

Study of Equations (B-16) and (B- 17) is difficult because they are complicated. 

Let us try various coordinate transformations in order to simplify them. 

First establish the coordinates for the image of the horizon line. The horizon 

line is the line for which yg oo. Inspection of (B- 13) shows that y co when g 

the denominator 0 or 

S0xiH +Sp

C

0

y. +CC0F= 0 (B- 18) .H 

where x.1F1 and iH Y. are image plane coordinates of all points on the horizon. 

Now establish the coordinates for the image of the flight line. The flight line 

is the line for which x = 0. Inspection of (B-12) shows that x g = 0 when the g 

numerator is zero or 

C0xiF -SpSe

y. 

P° 

0 (B- 19) 

where x. and . are image plane coordinates of all points on the flight line. iF 

This document contains information affecting the national defense of the United States within the mooning of the Espionage Laws, Title 

B. U.S.C„ Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by low. 
UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

Now determine the point where the horizon line and flight line intersect. Call 

this point the vanishing .point with coordinates xiv, yiv. This point is the 

simultaneous solution of (B-18) and (B-19), yielding 

C 

x. = 0, y. = -F (B-20) 

Now translate the coordinate system in the image plane such that its origin is 

at the vanishing point, or let 

X. = X 1 v 

C 

yl =yv - F 2- 

Substituting (B-21) into (B- 16), (B- 17), (B- 18), and (B- 19) yields 

x 

. 1 V 

v 

= — — F H S

p

x

v

(S

e

x

v + SPC0yv) 

(B-21) 

(B-21a) 

and 

and for the horizon line 

and for the flight line 

iry= 

v

Sp yv(Sexv+ SpCoyv) 

SOxvH + SpCO YvH = 

S

e

x

vF - S

p

SyvF 0 

‘iNCL

kSgi imIIED 

(B-22) 

(B-23) 

(B-24) 

This document contains information affecting the national defense of the united Stales within the meaning of the Espionage Laws, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by low. 
1 

(0 

S 

S 

X P x + y) 

v 

 = 

1 + To 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

Now rotate the coordinate system such that the horizon line is in the x 

direction. In order to accomplish that let 

(B-25) 

and 

Yv (B-26) 

Substituting (B-25) and (B-26) into (B-21), (B-22), (B-23), and (B-24) yields 

S 

To 

)2 0 (S 

P + y = +

1 V S

pSo1 + y T

P x + 

S )2 S 

T = 1 V S So il + (,r2- y( x_ TP 

0 

YH = 

SeCeCoo 

xF T YF = ° 

(B-27) 

(B-28) 

(B-29) 

(B-30) 

Multiplying (B-28) by Sp /Toand subtracting from (B-27) yields 

Y= 1 V S 

p

S

e 

 1 + (SP) y2 (B-31) 

UNCLAStIFIED 

This document contains information affecting the national defense of the United States within the meaning of the Espionage Laws, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to an unouthorized person is prohibited by low. 
(B-32) 

(B-33) 

)2 

F H 

. 1 V x = — — S S01+ +

To 

xy 

p 

The optical axis is given by 

xis = y. = 0 is 

(B- 34) Yvo = FI T 

Substituting (B-33) into (B-21) yields 

x = 0 

vo 

• x (B-35) 

o 

- -F 

S )2 

1 + 

C 

yo- F 

S 2 

TO + (4-) 

JO 

(B-36) 

= K l y2 

= K1

xy 

UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

Multiplying (B-27) by Sp /Toand adding to (B-28) yields 

Substituting (B-34) into (B-25) and (B-26) yields 

where x

o 

and y

o 

are the coordinates of the optical axis in the final camera 

coordinate system. 

We are now prepared to analyze our image motions. Consider Equations 

(B-31) and (B-32). It can be seen that, for a given satellite altitude, camera 

focal length, and orientation the only variables are X, jr, x, and y. That is 

This document contains information affecting the national defense of the United Stales within the meaning of the Espionage Laws, Till. 

18, U.S.C., Section 793 and 704, the transmission or revelation of which in any manner to an unauthorized person is prohibited by low. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

where 

K = 1 V S 1 -f S

p e +To 

and is constant for a given picture taking mission. 

Let us examine (B-36) closely. It can be seen that the image velocities vary 

non-linearly across the image plane. Therefore rotations about the optical 

axis or other point or zooming cannot possibly correct for image plane errors 

because these motions provide linear corrections. We may therefore conclude that 

No framing camera can possibly be built for forward and 

side-oblique photography with proper IMC across the image 

plane with exclusively linear compensations such as lens 

motions, film motions, camera rotations, and zooming. 

Let us now consider a strip camera. In such a camera, IMC is not required 

across the entire image plane but is required merely on one line in the image 

plane. When a slit is chosen such that 

Y = Yo (B-37) 

and (B-37) is substituted into (B-36), it is found that 

= K iy02 which is constant , 

(B-38) 

and x = (Kiyo)x which is linear in x 

It is therefore found that image velocities perpendicular to the slit (jr) are 

constant and can be removed entirely by film travel. It is also find that image 

velocities along the slit (X) are linear with position on the slit and therefore can be 

removed entirely by a combination of film travel and continuous image size change 

UNCLASSIFIED 

This document contains information affecting the national defense of the United States within Ilse meaning of the Espionage Lows, Title 

18, U.S.C., Section 793 and 794, the transmission or renelotion of which in any manner to on unauthorized person is prohibited by law. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

which might be accomplished by continuously varying the foCal length as 

accomplished by a zoom lens system. We may therefore conclude that 

A strip camera can be built for forward and/or side 

oblique photography, with theoretically perfect IMC 

provided we allow for film travel and zooming, and 

also provided that the slit is horizontal (equivalent 

to saying that y = constant). It should be pointed out 

that the straight side oblique situation is a special 

case and can be compensated only by film travel, 

rotation and translation of the film platen. 

The discussion will now be restricted to a strip camera for forward and 

forward-side-oblique photography. Let us now consider the image motion 

that must be corrected in the strip camera. 

Place the slit so that it is horizontal and contains the optical axis. Let the 

coordinates of the slit be (xs' y

s

). Since the slit is horizontal: ys= yo. 

From (B-35) we have 

C 

• 

ys= F 

S 2 

(B-39) 

1 + -2- 1 

) 

T

E) 

Further let 

x

s 

= x

o 

+ Ax (B-40) 

where 

Ax is position along the slit measured with respect to the 

optical axis. 

Substituting (B-35) into (B-40) yields 

X

s 

= AX — F 

• P 

T / )1 + SP 2 Te 

URIC FOE® 

(B-42) 

This document contains informotion affecting the national defense of the United States within the meaning of the Espionage Laws, Title 

IS, U.S.C.. Section 797 and 79e, the transmission or revelation of which in any manner to on unouthorised person is prohibited by law. 
ys = (B-42) 

c 

2

c 

V P e 

"L.H (S )2 To 

+ TP 6 

and 

2 C C V P Xs

= -F + 

V S C C Ox 

1 

IS 2 )

H ppe 

\ T61 

(B-43) 

• 

U r \1 C 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• Substituting (B-39) and (B-41) into (B-31) and (B-32) yields 

From (B-42) and (B-43) the image motion on the optical axis is 

yo = F1V-1 

CP C8 

p 0 

S )2 To 

1 +(--,r0 1-3

(B-44) 

2 

X = _ FV 

C PC 0 

o H + (S p)2 

TO 

If we translate the film such that the image motion on the optical axis is 0, 

then this is tantamount to subtracting (B-44) from (B-42) and (B-43), yielding 

jrs= 0 px = HSp  C PC 

o

/Ix (B-45) 

Let us now consider the zooming phenomenon. 

This document contains information affecting the national defense of the United States within the meaning of the Espionage Lows, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of wh;,), in any manner to an unauthorized person is prohibited by low. 
(B-46) 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 , 

Let 

where 

ailairi CL ff 

Ax z= F tan ct 

(B-49) 

If the zooming is proper, then the image motion, caused by zooming, just 

cancels the residual image motion due to satellite travel, or 

Ak + 6,5c

z 

= 0 

Substituting (B-45) and (B-48) into (B-49) yields 

s c (B-50) ppc H = 

Axzis the position on the image plane measured with respect 

to the optical axis 

F is the camera focal length 

a is the angular direction of the principal ray measured 

with respect to the optical axis. 

If we change the focal length as a function of time (zooming) then the resultant 

image velocity is found by differentiating (B-46) or 

Aic

z 

= F tan a 

where 

Ak

z 

is the image velocity caused by zooming 

F is the time rate of change of focal length. 

Substituting (B-46) into (B-47) yields 

Ax

z 

(B-47) 

(B-48) 

UNCLASSIFIED 

This document contains information affecting the national defense of the United Stales within the meaning of the Espionage laws, Title 

18, U.S.C.. Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by law. 
UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

Solving the differential Equation (B-50) yields 

V F = F

o 

exp(- —H S

p

C

p

C

O

O (B-51) 

where F

o 

is the focal length at time = 0. 

Finally, the image motion at the optical axis that must be cancelled by film 

travel is found by substituting (B-51) into (B-44), yielding 

V 

iro = Fo H 

C

2

C Sp 

P 0 exp(- 

S P 

C 

 P C0 

 t) 

(

S

p - 

)2TO 

1 + JT

- 

(B-52) 

C C P 0 exp(- S C C (S )2 P P 0 / 

V ko = -F — o H 

TO 

The total image motion at the image plane, thus will be the square root of the 

sum of the squares of Equations (B-52), i. e. , 

Vio=iy

o+5c o =FoH YC2 exp(iT SpCpCot) (B-53) 

UNCLASSIFIED 

11111111.11.1111111111 

This document contains information affecting the national defense of the United States within the meaning of the Espionage Laws, Title 

18, U.S.C., Section 793 and 794. the transmission or revelation of which in any manner to on unauthorized person is prohibited by law. 
NRO APPROVED FOR 

UNCLASSIFIED 

RELEASE 1 JULY 2015 

APPENDIX C 

SOME ERROR ANALYSES AND DESIGN DETAILS FOR THE FORWARD 

AND SIDE-OBLIQUE STRIP CAMERA 

I. QUESTION 

What must be the initial setup for the camera to have proper IMC? 

Analysis 

If the satellite, having a vertically oriented camera, is first rolled and then 

pitched to place the camera into position, then the image velocities in the 

focal plane are given by equations (B-16) and (B-17). From these equations 

we may determine the image motion on the optical axis, as 

xi = y. = 0 (C- 1) 

Substituting (C- 1) into (B- 16) and (B- 17) yields 

x. = 

•(C- 2) 

'r. = F C2Co 

From (C-2) we see that the image motions are restricted to the yiaxis. This, 

in turn, means that the mechanisms causing film travel for IMC purposes are 

already properly oriented. 

Let us now consider slit orientation. From (B-39) we have the relation that 

the slit equation is given by 

C 

(C-3) Y = F 

T 71 + 0 TO 

UNCLASSIFIED 

This document contains information affecting the national defense of the United States within the meaning of the Espionage Laws, Title 

18, U.S.C,, Section 793 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by low. 
NRO APPROVED FOR 

UNCLASSIFIED 

RELEASE 1 JULY 2015 

• 

Solving (B-25) and (B-26) simultaneously for y yields 

1 

z v+ Tov) 

iSTp 

ei 

(C-4) 

Eliminating y between (C-3) and (C-4) yields 

C S 

F= x +- E y To v Tov 

Substituting (B-21) into (C-5) yields 

TO Co- C 

Yi = xis + F 

(C-5) 

(C-6) 

From (C-6) we find that the slope of the slit line is given by 

Or 

tan a = 

tan 0 (C-7) 

sin p 

To 

S 

• 

where 

a is the rotation of the slit with respect to its position in 

vertical photography 

0 is satellite roll angle 

p is satellite pitch angle 

UNCLASSIFIED 

101111111111111111111 

This document contains information affecting the national defense of the United Slates within the meaning of the Espionage Laws, Title 

I 8, U.S.C., Section 793 and 79e, the transmission or revelation of which in any manner to on unouthorixed person is prohibited by low. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

earkilias 

• If we make the following restrictions: 

a) Satellite roll is less than satellite pitch 

b) Roll and pitch can be as great as 45° 

then the amount that the slit must be able to rotate is 

a = tan

-1 tan 45° - 55° 

sin 45 

(C-8) 

Conclusions 

1) If the satellite is first rolled and then pitched into position, 

then no rotation of the film travel mechanism about the 

optical axis is required. 

2) The slit must be able to rotate ±55°from nominal position. 

II. QUESTION 

How wide can the slit be for exposure purposes? 

Analysis 

The component of image motion perpendicular to the slit in the neighborhood 

of the optical axis is given by (B-31) 

S 

= —1 VS 11 P2 

0 F 171 S -.p 0 + 0 yo 

The variation in image motion in this neighborhood is given by 

(C-9) 

. djr 

AYo =AYo 

o 

(C-10) Or 

AY0= Tr'p-0 Te 0 VS 1 +1) Ay() 

UNCLAgSIFIED 

This document contains information affecting the notional defense of the United States within the mooning of the Espionage tows, Title 

18, U.S.C., Section 703 and 794, the transmission or revelation of which in 007.0000, to on unoutherized person is prohibited by tow. 
UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

The fractional error of image motion E at the edge of the slit is given by 

Air° 

E = 

yo 

Substituting (C-9) and (C-10) into (C-11) yields 

E yo 

Ay =2 

Substituting (B-35) into (C-12) yields 

EFCp 1 

6'y - 2T0 s

2 

1 + P T O 

(C-11) 

(C-12) 

(C-13) . 

The slit width is most restricted when the denominator is a maximum and the 

numerator is a minimum. This is equivalent to stating that the slit width is 

most restricted when both 0 and p are maximum. Therefore let p = 0 = 45° . 

Substituting these values into (C-13) yields 

Ay = 0. 29eF (C-14) 

If we assume that E = 10-3 and F = 240 inches then Ay is restricted to widths 

narrower than 0. 07 inch. 

Ay = 0. 07 inch. (C-15) 

UNCLASSIFIED 

This document contains information offecting the national defense of the United Stotes within the meaning of the Espionage Lows, Title 

Ia. U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by law 
E 

t

max 2 —V 

H pCpC0 S 

(C-17) 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

Conclusions 

If we allow pitch and roll to be as great as 45° , and we restrict image motions 

to vary less than 0. 1% anywhere in the slit, then the maximum slit width for 

a 20 foot focal length camera is 0. 07 inch. 

III. QUESTION 

What is the maximum allowed exposure time? 

Analysis 

The maximum allowed exposure time is given by 

t

max 

= 

jro 

(C-16) 

Substituting (B-35), (C-9), and (C-13) into (C-16) yields 

Substituting the following values 

E = 10-3 

V = 4 X 10-2 at an altitude of 100 n mi 

p = 0 = 45 ° 

into (C-17) yields 

1 

t

max 

= —14 sec. 

Conclusions 

The camera must be designed so that the slit widths restrict exposure times 

to less than 1/14 second at 100 n mi. Further, maximum allowed exposure 

time is inversely proportional to V/H. • 

UNCLASSIFIED 

MOM 

This document contains information offecting the notional defense of the United States within the meaning of the Espionage Lows, Title 

IS, U.S.C,, Section 793 and 794, the transmission or revelation of which in uny manner to on unauthorized person is prohibited by low. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLASSIFIED 

AIM 

• 

IV. QUESTION 

What is the zoom rate and maximum ratio? 

Analysis 

Equation (B-51) gives the form of the zoom to be 

V F = Foexp(- RspCpCet) (C-18) 

where F

o 

is the initial focal length 

F is focal length at some time t 

The total image motion in the image plane at the optical axis Rois given by 

the square root of the sums of the squares of equations (B-52) or 

k 3.(2 

o 70 • 0 

or 

Ro= Fo-111 V -CpCoexp(- SpCpC0t) (C-19) 

The total length of the exposure Rois given by the integral of (B- 19) 

t

max 

R

o 

=

o

dt 

I 

or 

F V 

Ro T

o 

--H = [1 - exp (- S

p

C

p max

Cet )] (C-20) 

UNICLA MED 

This document contains information affecting the national defense of the United States within the meaningof the Espionage Lows, Title 18, U.S.C., Section 793 and 794, the tronsmistion or revelation of which in one manner to on unauthorized person is prohibited by low. 
R

o t (C-22) 

max V 2 F

o 

—H C

p

C

O 

NRO APPROVED FOR 

RELEASE1 JULY 2015 

UNCLASSIFIED 

• Since the exponent tends to be quite small, we may approximate 

exp

v

S

p

C

p

C

e

t

max

) 1- V S

p

C

p

Ct 171 0 max 

Substituting (C-21) into (C-20) yields 

V 2 R

o 

= Fo H C

p

C

O

t

max 

or 

(C-21.) 

Substituting (C-22) into (C- 18) yields 

F . = FO 

Expansion of the exponential into an infinite 

TpR0 1 

R 

yields 

TpR03 

(C-23) 

(C-24) 

exp(-Tp .t. 0 

series 

TpR02 1 

Fmin= F0 [ 1 - +21 F

o 

F

o 

E F

o 

The servos will be reasonably simple if the fourth term in the series can be 

neglected. This is possible only if (for a 0. 1% IMC system) 

T

3

R

3 

1 P ° - 10-3 

-6 -3- F

o 

UNCLASSOFIED 

(C-25) 

This document contains information affecting the notional defense of the United Stoles within the meaning of the Espionage Lows, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in any monner to on unouthorited person is prohibited by low. 
(C-26) 

4110 entiating (C- 18) yields 

v s P c P —H ce (exp - S

p

C p

Cot) 

0 

NRO APPROVED FOR 

RELEASE 1 JULY 2015. 

• 

or • 

F 

R

o 

0. 182 T

° 

p 

If we assume a focal length of 20 feet and a forward pitch angle of 45°then 

the frame length Rocan be 3.6 feet long when the camera is pitched 45°forward. It can be longer if the camera is pitched less. 

Substituting (C-25) into (C-23) yields 

F

. = exp - 0. 182 = 0. 834 

This implies that the focal length will never have to decrease more than 17%. 

Let us now determine the maximum rate of zoom that is required. DifferInspection of (C-26) shows that the rate is maximum when 

V 14is maximum (0. 04) 

p = 45 ° 

= 0 

t = 0 

Substituting these values into(C-26) shows that 

= 0. 02 

( o)max 

UNCLAsS$11FEED 

WM* 

This document contains information affecting the national defense of the United States within the meaning of the Espionage LOWS, Title 

IS, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by law. 

F

o 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLASSIFIED 

This result shows that the maximum possible zoom rate (as well as film 

speed change rate) under the worst conditions never exceeds 2% per second. 

Conclusions 

The analysis above shows that for a frame format at least 3.6 feet long the 

zoom rate never exceeds 2% per second. The maximum zoom never exceeds 

17%. Longer frame formats are possible at the expense of an increase in 

maximum zoom and the introduction of some non-linearities in the zoom rate. 

UNCLASSEIFED 

This document contains information affecting the national defense of the United States within the meaning of the Espionage lows, Title 

IS. U.S.C., Section 799 and 794, the transmission or leyetotion of which in ony manner to on unauthorized person is prohibited by low. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 • 

• 

UNCLASSIFED 

- APPENDIX D 

PRELIMINARY DESIGN CONSIDERATION ON A HIGH ACCURACY 

FILM DRIVE MECHANISM 

1. 0 INTRODUCTION 

A parametric study and analysis was made to develop and evaluate a high 

accuracy mechanical film drive capable of permitting very high resolution 

photography when coupled to a nearly defraction limited lens system. The 

system was considered for performance in a space vehicle. Design consideration was given to four modes of operation: 

a. vertical 

b. side-oblique 

c. forward and backward-oblique 

d. forward and backward side-oblique 

Two film drive systems were developed to accommodate for operational modes 

a, and a + c. Two optical configurations are suggested to solve mode b. The 

chosen optical solution for b can be used with either film drive in a final 

photo-optical system design. 

2. 0 VARIOUS FILM DRIVE DESIGN APPROACHES 

A film drive capable of better than 0. 1% accuracy is required in order to 

deliver maximum resolution with very long focal length lenses of nearly 

defraction limited design and to meet the system requirement of 0. 1% IMC. 

Lacking specific design parameters, the following criteria were assumed: 

Assumptions: 

Film 

width: 12.5 in. 

length: 100 to 1000 ft 

thickness: 0. 003 in. 

weight: approx. 24 lb/ 1000 ft 

This document contains informotion affecting the notional defense of the United Stoles within the meaning of the Espionage Lows. Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in ony manner to on unouthorized person is prohibited by low. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• Lens focal length: 25 ft 

IMC speed (V): 4 to 8 inches per sec 

Max. angular rate: 1-3/4 deg/sec total angular motion 

(t = 6 ° ) 

Side motion (V. ): 0. 3 inch/sec max 

Total translation or side motion: 0. 50 in. (design for f 0.5 in.) 

Running time per frame: 6 seconds 

Forward or backward obliquity angle: not to exceed 30 degrees 

Design commenced with a rather orthodox but proven drive as shown in 

Figure D- 1. The system consists of nine units positioned successively from film 

supply to film take-up. Power is applied to the film drive system at four 

different points; i. e. , the supply metering roller, the platen drive motor, 

the take-up metering motor, and the film take-up reel motor. The film is 

kept under tension from supply to the metering rollers by a braking action at 

the supply reel. The platen drive motor provides speed control for the movement of the film across the slit at the appropriate speed. 

Film tension between the two metering rollers should be held constant at 

about 3 to 5 pounds by constant tension springs (negator springs) in the two 

platen loopers. Tension between the metering rollers and the supply or takeup reel will vary from 1 to 10 pounds. The tension is controlled by a set of 

springs in the two tension loopers. 

The four loopers in the system serve to provide smooth operation by controlling the film tension and help to keep the system in dynamic balance by 

activating and de-activating certain components in the system. 

A more sophisticated design of a. film and platen drive is suggested in 

Figure D-2. Here, power to the film drive is applied only in three points, 

one of the motors (in the film supply drum) being used also as a brake. The 

platen for the system of Figure D-2 is identical to the platen for the system 

of Figure D-1. The two loopers are coupled mechanically. A system of this 

type is more sensitive to 'banding' due to uneveness in film transport, but if 

UN LAESIFIED 

This document contains information affecting the notional defense of the United States within the meaning of the Espionage Laws, Title 

18. U.S.C., Section 793 and 794, the transmission or re•elation of which in ony manner to an unauthorized person is prohibited by low. 
FILM 

TAKE- UP 

FILM 

SUPPLY 

PLATEN LOOPER 

TAKE-UP PLATEN 

JVVV V4 

LOOPER 

SUPPLY 

PLATEN 

LOOPER 4. 

TAKE-UP TENSION 

TAKE-UP 

METERING 

ROLLER 

LOOPER 

SUPPLY 

TENSION 

METERING 

ROLLER SUPPLY 

BRAKE CLUTCH 

ROLLERS ROLLERS 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

Figure D-1. Schematic of Film & Platen Drive for Conventional 

Aerial Camera 

UNCLASSIFIED 

This document contains information affecting the notional defense of the United Stoles within the meaning of the Espionage Lows. Title 

" 18. U.S.C., Section 793 and 79d. the ttensmission or revelation of wh,h in any ;rennet to an unauthorized person is prohibited by low. 
FILM 

TAKE-UP 

FILM 

SUPPLY 

TAKE-UP 

LOOPER 

SUPPLY 

LOOPER 

PLATEN 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLASSIFIED 

11.1111.111 

Figure D-2. Schematic of Film & Platen Drive for Advanced Aerial Camera 

UNCLA$SIFIED 

MIEN 

This document contains information effecting the national defense of the United Stales within the meaning of the Espionage laws, Title 

is. U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by law. 
UNCLASSI 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

carefully designed and built, -should prove superior to the one in Figure D-1. 

Film tension throughout the system would be approximately the same as in 

the Figure D- 1 system. Operation would be as follows: 

On a given command a d-c voltage is supplied to the take-up 

reel motor. An a-c voltage is supplied to the film supply 

reel and the platen. Both are synchronous motors with variable 

frequency speed control. The motor on the film supply reel is 

also used as a brake to control the momentum of the film supply 

reel. A hysteresis clutch in the film take-up drive permits 

variable slippage in the drive to compensate for the varying 

diameter of the take-up reel. Both reels also have locking 

brakes which are engaged when power is off to prevent the 

reels from turning and to retain film tension in the system 

during "off" periods. The film tension maintained in Figure D-2 

will vary from approximately 1 pound when the supply looper is 

full, to 6 to 8 pounds with the supply looper empty. Hysteresis 

brake torque will vary accordingly from about 8 foot pounds to 

zero with about 3 foot pounds at midposition. 

Figure D-3 shows a possible first design approach to the rotary platen 

problem. Besides a variable IMC speed, Y motion controlled by an adjustable 

cam and Z adjust are provided. Rotation of the total system is shown in two 

places, one for gross adjust and one for programmed motion. 

Figure D-4 is a further development of the design approach shown in 

Figure D-3. Only a single system rotation plane is provided and the Z adjust 

has been eliminated. The drum is rim driven rather than through gears to 

eliminate vibration. 

The Film Flow Schematic of Figure D-5 is similar to the one shown in 

Figure D-2. Wobble rollers as well as clutch and brake rollers were added 

to permit side and rotary motion of the film drive independent of the film 

supply and take-up which could then be located outside the camera proper. 

The design shown by Figure D-6 was developed after an engineering review 

of Figures D- 1 through D-5, with emphasis given to the possibility of short 

duration missions where perhaps only a hundred feet or so of film would be 

required per mission experiment. In this design a new approach to the take-up 

UNCLASWED Wriar" 

This document contains information affecting the notional defense of the United Stoles within' the mooning of the Espionage Laws, Title 

18, U.S.C., Section 797 and 794, the transmission or revolution of which in any manner to an unauthorized person is prohibited by law. 
UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

Sche

m

aticof FilmDrivePlaten 

UNCLASSIFIED 

This document conloins information affecting the notional defense of the United Status within the tneoning of the Espionage Laws, Title 

IA, U.S.C., Section 793 end 794, the tionqmission or I evelntion of which in try manner to an unauthorized person is prohibited by low. 
..•—••••• 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

Y-CAM AND FOLLOWER 

DRUM -TYPE PLATEN 

zzzzzzzz ..zzzz 

• 

Y-ADJUST 

MOTOR 

f 

n, " V, 

e • I . 

Y-AJUST 

Ifs 

PLATEN DRIVE MOTOR 

Figure D-4. Schematic of Design Variation of Film Drive Platen 

D-7 

This document contains information affecting the notional defense of the United Stales within the mooning of the Espionage lows, Title 

I ft, U S.C., Sr.:Irian 793 and 794, the transmission or revelation of whi.h in any manner to an unauthorized person is prohibited by low. 
• 

. NRO APPROVED FOR 

RELEASE 1 JULY. 2015 

Revised 4 Nov 1965 

UNCLASS11FOED 

MEW 

This document contains information affecting the notional defense of the United Slates within the meaning of the Espionage tows, Title 

IS, U.S.C., Section 793 and 794, the transmission or revelotion of which in any manna, to on unauthorized person is prohibited by low. 
I 

1 

12.5 IN. 

FILM 

-0201N. 

nCAMERA 

TRANSLATION 

CAMERA 

ROTATION MOTOR 

FILM 

SUPPLY 

-'20 IN. 

LOOPER TIE ARM 

Figure D-6. Schematic of a Compact Design Film Drive Rotary Platen 

^r 28 IN. 

FILM 

TAKE-UP 

UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 saw 

METERING ROLLERS 

UNCLA 

This document contains information affecting the notional defense of the United Stales within the mooning of the Espionage Lows, Title 

lg. U.S.C.. Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by law. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

looper has been made. This new design and the reduced film roll size make 

for a rather compact and clean design. This study also brought out the 

possible need for a rotating slit in the camera should side-oblique photography 

be attempted. 

Figure D-7 represents a design concept for such a film drive camera body. 

Note that the rotating platen has been abandoned and its place is taken by a 

slit-platen combination that has minimum contact with the, film and can be 

rotated through ±45 degrees. A design of this type would present a real 

engineering challenge. The relatively long stretch of unsupported film in the 

focal plane area, running at considerable IMC speed, would be difficult to 

keep from oscillating and precise flatness in the focal plane would be most 

difficult to maintain. These considerations prompted the development of a 

new drive concept in which a belt-loop is employed as a constant film speed 

drive medium (Figures D-8 and D-9) and/or as a film support and transport 

medium (Figure D-10). 

Figures D-8 and D-9 show variation of the drive belt integration into a film 

transport system. Only a single motor is needed for such a transport design 

but difficulties such as film spill from a full supply roll could be encountered 

when the drive is stopped too fast. A separate brake on the film supply spool 

might be needed. 

Figure D- 10 elaborates on the belt-drive idea extending the drive to carrying 

the film in a conveyor-like fashion over a platen and by the exposure slit. A 

system of this kind would do very well in an earth environment and could also 

be used in a framing camera system. The drive-film transport belt might be 

made of a porous material that would permit a vacuum application to the film 

to hold it flat in the focal plane. 

Figures D-11 and D-12 show the application of the constant film velocity drive 

to a rotating platen slit camera. Such a design approach would possibly prove 

equal to or better than the more sophisticated drive designs if the camera 

UNCLWREFOED 

11111111r 

This document contains information affecting the notional defense of the United States within the meaning of the Espionage Laws, Title 

18, U.S.C., Section 793 and 794, the transmission a, revelation of which in any manner to en unauthorized person is prohibited by law. • 
FILM TAKE-UP FILM SUPPLY 

CAMERA 

TRANSLATION 

\--SLIT 

ROTATION 

UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

Figure D-7. Schematic of a Compact Design Slit Camera Film Drive 

Employing a Rotating Slit Plate biz Film Back-up at 

Focal Plane 

UNCLASSIFIED 

10111110 

This document contains information affecting the notional defense of the Un:ted Stoles within the mooning of the Espionage Laws. Title 

18. U.S.C., Section 793 and 794, the loantmission or revelation of which in one manner to on unouthorized person is prohibited by low. 
UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLIV*6 FEED g

MOM 

This document contains information affecting the nationol defense of the United Stales within the meaning of the Espionage tows, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by low. 

FigureD-8. Schematicof a ConstantSpeed FilmDrive 

• 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLASSIFIED 

CONSTANT SPEED DRIVE 

DRIVE MOTOR 

. DRIVE BELT 

FILM SUPPLY 

FILM TAKE-UP 

/FILM 

Figure D-9. Schematic of a Variation of a Constant Speed Film Drive 

UNCLASSIFIED 

Mar 

This document contains information affecting the national defense of the United States within the meaning of the Espionage Lows, Title 

Ie. U.S.C., Section 793 and 794, the transmission or reuelation of which in any manner to on unauthorized person is prohibited by tow. 

• 
74 

 DRIVE BELT AND 

FILM SUPPORT 

( 

SUPPORT PLATEN 

EXPOSURE SLIT 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

Figure D-10. Schematic of Constant Speed Film Drive Employing 

a Drive-Film Support Belt in a_ Slit Camera 

UNCLRailFIJED 

MI& 

This document contains information affecting the national defense of the United States within the meaning of the Espionage Lows, Title 

Sertion 793 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by low. 
FILM 

TAKE-UP FILM SUPPLY 

CONSTANT SPEED 

FILM DRIVE 

DRUM TYPE 

PLATEN 

\—EXPOSURE SLIT 

UNCLASSiFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 BMW 

• 

Figure D-11. Schematic of Constant Speed Drive in Rotating 

Platen Camera 

UNCL'AeSEIFQED 

111.111111111 This document contains information affecting the notional defense of the United States within the mooning of the Espionage lows, Title 

IS. U.S.C., Snctinn 793 and 794, the f tansmission or revelation of which in any nlonner to on unouthori2ed person is prohibited by low. 
FILM 

TAKE-UP FILM SUPPLY 

CONSTANT SPEED 

FILM DRIVE 

DRUM TYPE 

PLATEN 

-7 VUNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 AIM 

EXPOSURE SLIT 

Figure D-12. Schematic of Design Variation of Constant Speed Drive in 

Rotating Platen Camera 

UNCLMSIIFIE 

this document cantoins information affecting the national defense of the United States within the meaning of the Espionoge laws, Title 

19, U.S.C.. Section 703 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by low. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 • 

UN 

• 

drive could run continuously.- The design might become marginal in a stop 

and go application because of the large mass acceleration and deceleration 

with possible spilling of film, etc. 

Figures D- 13 and D- 14 sum up schematically the two film drive approaches 

considered feasible. Figure D- 13 would be the more orthodox and proven 

design, but is incapable of coping with the forward side-oblique situation. 

Figure D- 14 will require considerable engineering R&D, but once solved 

could be used in many applications. The need for holding the film flat in the 

gate is obvious, as is the control, of vibrations, drag, etc. Considerations 

of these problems led to the design Figure D-15. In this camera configuration a separate dampened film support belt is used in conjunction with a 

closed loop vacuum/pressure system at the focal plane. The exposure slit 

and camera can rotate about the optical axis while the whole system is 

capable of translating sideways. Figure D- 16 shows a possible solution for 

a drum-slit system design along the lines previously discussed. As mentioned 

before, the design is considerably more orthodox than the one shown in 

Figure D-15. Considerable design complexity could be avoided if the forward 

side-oblique case is not a requirement. 

The IMC problem resulting from forward and back-oblique photography can 

be solved by the introduction of a re-imaging system and by purely mechanically moving a number of mirrors to lengthen or shorten the light paths. A 

preferable approach would employ a re-imaging system designed to zoom the 

appropriate amount during exposure. Figure D-17 shows the two approaches 

schematically and Figure D- 18 shows a schematic of the lens system employed. 

3. 0 CAMERA DESIGN 

3. 1 FILM DRIVE CONSIDERATIONS - SUMMARY 

A progression of film drive designs was investigated in an attempt to determine an optimum design which would meet the high accuracy requirement of 

this system. As a result of these analyses two design approaches are 

UNC L • gpFlIED 

111•111111P 

This document contains information affecting the notional defense of the United States within the meaning of the Espionage taws. Title 

18. U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to on unouthorixed person is prohibited by low. 
OPTICAL 

AXIS I MC 

(IMAGE MOTION COMP) 

SIDE OBLIQUE 

COMPENSATION 

/// / //// / / 

TRANSLATIONAL 

LEAD SCREW 

 FLIGHT LINE 

NRO APPROVED FOR • 

RELEASE 1 JULY 2015 

Revised 4 Nov 1965 

Figure D-13. Film Transport System for Vertical or Side-Oblique 

Photography Employing a Drum-type Platen 

UNCL FED 

MN! 

This document contains information affecting the notional defense of the United States within the mooning of the Espionage Lows, Title 

18, U.S.C., Sestion 793 end 794, the transmission or I evelation of which in coy manner to an unauthorized person is prohibited by low. 
FILM 

TAKE-UP 

TAKE-UP LOOP 

BEARINGS 

SUPPORT BELT 

IMAGE MOTION COMPENSATION 

FORWARD SIDE OBLIQUE (OR BACK SD) 

COMPENSATION • 

OPTICAL AXIS 

SIDE OBLIQUE 

COMPENSATION 

TRANSLATIONAL 

LEAD SCREW /// / //z/zez/z/&////// 

v. FLIGHT LINE 

NI O APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLASSIFIED 

Revised 4 Nov 1965 

Figure D-14. Schematic of Film Drive Employing Rotating Expostire 

Slit Plate & Film Support Belt at Focal Plane 

UNCLAMMFIIED 

111111111P 

This document contains information affecting the national defense of the United States within the meaning of the Espionage Lows, Title 

10, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by low. 
Revised 4 Nov 1965 

0 

CAMERA TRANSLATION 

41 

4-1 

cd 

04 

0 

-o 

ca 

on 

k 

ra, 

•-• fx-1 

as 44 

4-4 

• (I) 

0.0 4—,z; 

UO3 E° 

cd 

▪ 

o0 

O 0 

(1 

,.., 

e2C 

Figure D- 15_ 

FILM TAKE -UP 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLASOPHED 

OM' 

This document contains information affecting the national defense of the United States within the meaning of the Espionage Laws, Title 

18, Section 793 and 794, the transmission or rove lotion of which in any manner to an unauthorized person is prohibited by low. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

161111164 

ATTACHMENT TO FIGURE D-15 

Film Width: 12. 5 in. 

Film Thickness: 0. 0053 in. (SO-243) or 0. 0025 in. (4404) 

Film Core Dim. 

& Weights: a) Universal Aerial Film Core/Flanges 

Core dia.: 4. 25 in. (0. 125 in. thick M 

Flange Dia.: 8. 0 in. (0. 295 in. Al) 

Spool will hold 500 ft. of SO-243 (19.5 lb) 

1000 ft of 4404 (23 lb) 

Empty spool will weight approx. 3. 5 lb each 

b) Spool-Aerial Roll Film (USAF 51C17848) 

Core dia. 2.12 in. (Al 1/16 in. thick) 

Flange dia. 4.12 in. for 100 ft (0. 005 film) 

5.94 in. for 250 ft (0. 005 film) 

Note: The 4. 12 reel will take 'N.,300 ft and the 5. 94 

reel, take ti 700 ft of 0. 0025 film. 

Weight of spool empty: 0. 75 lb and 1. 00 lb 

Weight with 0.0053 film, 100 ft - 4.6 lb, 250 ft - 10.6 lb 

Weight with O. 0025 film, 300 ft - 7.65 lb, 700 ft - 16.5 lb 

Film Belt: Width:13 inches 

Thickness:-- 0. 06 in. 

Weight:— 0. 30 lb/ft = 1. 25 lb 

Running speed:4 to 8 in. /sec 

Film Drive: Drive rollers (2):1. 5 in. dia. , 66 - 132 RPM, 1 lb each 

Film slit mech. weight: — 10 lb 

Film drive, total, exclusive of film: —65 lb 

Note: This is the assumed total weight of the mechanism to 

be translated and rotated. 

UNCLAttiFIED 

This document contains information affecting the national defense of the United Stoles within the meaning of the Espionage Lows, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by law. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

Revised 4 Nov 1965 

"I 0 

Y AXIS 

TRANSLATION 

UNC • gSEFEED 

FILM 

TAKE-'UP 

LOOPERS 

40"41 

FILM 

SUPPLY 

8 ROTATION 

Figure D-16. Schematic of Rotary Drum Film Drive Providing Freedom 

in Y Axis and Rotation above q, (A) 

This document contains informotion affecting the notional defence of the United States within the mooning of the Espionage Laws, Title 

18, U.S.C., Section 793 and 79e, the tionsmission or revelation of which in ony manner•to an unauthorized person is prohibited by law. 
NRO APPROVED FOR 

RELEASE .1 JULY 2015. 

ATTACHMENT TO FIGURE D-16 

Film Width: 12. 5 inches 

Film Thickness: 0. 0053 in. (SO-243 or 0. 0025 in.) (4404) 

Film Core Dim. 

& Weights: a) Universal Aerial Film Core/Flanges 

Core dia. : 4. 25 in. (0. 125 in. thick Mg) 

Flange dia.: 8. 0 in. (0. 295 in. Al) 

Spool will hold 500 feet of SO-243 (19.5 lb) 

1000 feet of 4404 (23 lb) 

Empty spool will weigh approx. 3. 5 lb each 

b) Spool-Aerial Roll Film (USAF 51C17848) 

Core dia.: 2. 12 in. (Al 1/16 in. thick) 

Flange dia. : 4. 12 in. for 100 ft (0. 005 film) 

5. 94 in. for 250 ft (0. 005 film) 

Note: The 4. 12 reel will take ti 300 ft and the 5. 94 

reel take ti700 ft of 0. 0025 film. 

Weight of spool empty: 0. 75 lb and 1. 00 lb 

Weight with 0.0053 film, 100 ft - 4.6 lb, 250 ft - 10.6 lb 

Weight with 0.0025 film, 300 ft - 7.65 lb, 700ft - 16.5 lb 

Drum Dimensions 

& Weight: 12 in. dia x 13 in. long 

rotation approx. 6 RPM to 13 RPM 

weight approx. 10 lb (skin ti 7 lb) 

Camera weight without film: about 55 lb 

Drive rollers: approx. 1 lb each 

rotation about 60.- 120 RPM 

UNCLASSIFIED 

This document contains information affecting the notional defense of the United States within the meaning of the Espionage Lows, Title 

IB, U.S.C., Section 793 and 794. the transmission or revelation of which in ony manner to an unauthorised person is prohibited by law. 
PRIMARY 

OPTICAL 

SYSTEM 

RE-IMAGING. 

ZOOM SYSTEM—NSLIT 

FIELD LENS 1/4• 

MOVING 

MIRRORS PLATEN 

ZOOM 

COMPENSATION 

OF SMEAR 

COMPONENT 

OPTICAL AXIS 

SHUTTER SLIT 

IMAGE MOTION 

COMPENSATED BY FILM IMC FLIGHT LINE 

AND OPTICAL AXIS 

Figure D-17. Re-Imaging System Schematic for Forward and Backward 

Oblique Photography 

UNCLAtSIFIED 

This document contains information affecting the notional defense of the United Stoles within the meaning of the Espionage Laws, Title 

18, U.S.C., Section 793 and 794, the t, ansmission or revelation of which in any manner to an unauthorized person is prohibited by law. 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

- PLATEN 
• 

UNC IFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

,48 IN. 

TOTAL WEIGHT: LB 

WEIGHT OF MOV. COMP: N 12 LB 

12 IN. 

 FILM 

PLANE 

12 IN. 

IMAGE 

PLANE 

Figure D-18. Schematic of Zoom Re-Imaging Lens System to Compensate 

for Forward and Backward Oblique Photography 

This document contains information affecting the notional defense of the United Stales within the meaning of the Espionage Laws, Title 

U.S.C., Section 793 and 794, the transmission on revelation of which in any manner to an unauthorized person Is prohibited by low. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

ATTACHMENT TO FIGURE D-18 

Weight & Design: Total weight: approx. 15 to 18 lb 

Weight of moving comp: 12 lb 

Maximum total motion: 0.60 in. assuming: 0. 20 in. /sec 

(total duration 3 sec). 

Note: It was assumed that only one forward and/or backward-oblique angle 

will be considered for stereo photography as it will be most difficult 

to sense the continuous change in focal length of the re-imaging lens 

and to drive the film accordingly at a continuously changing IMC rate 

to an accuracy better than 1/10 of one percent. 

UNCLA§bIFIED 

This document contains information affecting the national defense M the United Stoles within the meaning of the Espionage Laws, Title 

18, U.S.C., Section 793 and 794, the transmission or evelalien of which in any manner to on unauthorized person is prohibited by low. 
UNCLAb irgiao 

NRO APPROVED FOR 

• RELEASE 1 JULY 2015 

• 

suggested which are believed- to be within the realm of feasibility. A slit 

type camera appears to be the only choice for a non-camera tracking system. 

If only vertical or side-oblique photography is required, a more-or-less 

conventional drive system using a rotating drum platen may be employed. 

The accuracies which are sought are believed feasible, but extremely 

difficult to achieve. Figure D- 19 shows such a system schematically. 

Forward and backward plus side-oblique photography is of interest only if 

stereo photography is a requirement. Because of the necessity to rotate the 

slit at the focal plane, depending upon the obliquity angle, it is not feasible 

to employ a rotating drum platen: It might be possible to devise a belt backup 

drive system which could be held within the depth of focus tolerances. Sikh 

a system is shown schematically in Figure D-20. To fully compensate for the 

image motion, a zoom operation is required. This can most easily be accomplished as a re-imaging zoom system. The maximum zoom range for a four 

foot frame length was found to be less than 20%. 

4. CONCLUSION 

In conclusion it can be said that preliminary engineering considerations 

indicate the feasibility to design and build a camera film drive capable of 

moving film at the proper IMC speed and compensating for the error 

components due to any line-of-sight obliquity. It is questionable that the 

goal of a total error of 0. 1% or better can be achieved without considerable 

R&D, as well as prototype design and performance evaluation of a number of 

systems. 

UNCLIFIED 

an= 

This document contains information otlecting the notional defense of the United States within the meaning of the Espionage Laws, Title 

IT, U.S.C.. Section 793 and 794, the ttonstnistion or revelation of which in any manner to an unauthorized person is prohibited by law. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

Revised 4 Nov 1965 

UNCLASSIFIED 

WNW 

OPTICAL 

I MC AXIS 

(IMAGE MOTION COMP.) 

SIDE OBLIQUE 

COMPENSATION 

/// ////////////////////////////. // 

TRANSLATIONAL 

LEAD SCREW 

N.- FLIGHT LINE 

Figure D-19. Film Transport System for Vertical or Side-Oblique 

Photography Employing a Drum-type Platen 

LAIC' g8S1FOED 

This document contains information affecting the notional defense of the United Stoles within the meaning of the Espionage Lows, Title 

I8, U.S.C., Section 793 and 794, the transmission or revelation of which in ony manner to en unauthorized person is prohibited by law. 
FILM. 

TAKE-UP 

TAKE-UP LOOP 

BEARINGS 

SUPPORT BELT 

IMAGE MOTION COMPENSATION 

FORWARD SIDE OBLIQUE (OR BACK S.0.) 

COMPENSATION 

OPTICAL AXIS 

SIDE OBLIQUE 

COMPENSATION 

TRANSLATIONAL 

LEAD SCREW 

FLIGHT LINE 

NPO.AF'PROVED FOR 

RELEASE 1 JULY 2015 

UNCLAbbiFiLL) 

Mir Revised 4 Nov 1965 

Figure D-20. Schematic of Film Drive Employing Rotating Exposure 

Slit Plate & Film Support Belt at Focal Plane 

UNCIASWEED 

D-29 

ill11111IP 

This document contains information ef '0(1419 the notional defense of the United Slates within the meaning of the Espionage Lows, Title IS U.S.C.. Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by low. 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 AEROSPACE CORPORATION 

TECHNICAL REPORTS - DISTRIBUTION LIST 

REPORT TITLE 

1111. An Analysis of the Requirements for Very high 

Accuracy Image Motion Compensation 

REPORT NO. 

TOR 669(6107-40)-1 

INTERNAL DISTRIBUTION umC !FIED 

DATE 

October 1965 

SECURITY CATEGORY 

E. Alexander 

H. Bernstein 

J. Delangre 

F. Froom 

D. Gieseking 

R. Grove 

L. Hirschl 

F. Keller 

A. Mandl 

D. Martin 

D. Meronek 

D. McColl 

A. Nash 

J. Nines (2) 

H. Nordyke 

W. Sampson 

C. Sarture 

411 E. Silvertooth 

S. Tennant 

J. Thompson 

J. Travis 

R. Kardas 

L. Watson 

PREPARED BY • 

AEROSPACE FORM 2394 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 AEROSPACE CORPORATION 

TECHNICAL REPORTS - DISTRIBUTION LIST 

REPORT TITLE 

410,An Analysis of the Requirements for Very High 

Accuracy Image Motion Compensation 

DATE 

TOR 669(6107-40)-1 October 1965 

REPORT NO. 

EXTERNAL DISTRIBUTION 

SECURITY CATEGORY 

MOM 

UNCLASSIFIED 

MILITARY AND.GOVERNMENT OFFICES ASSOCIATE CONTRACTORS AND OTHER 

Wright Patterson Air Force Base 

ASD, Air Farce Avionics Laboratory 

H. R. Ilstwerdt, AVRP 20133 

L. W. Crouch, AVRP 29136 

F. A. Farinet, AVRP 20133 

PREPARED BY 

APPROVED BY 

(FOR AEROSPACE CORPORATION) 

•• 

(FOR GOVERNMENT I, GRAM OFFICE) 

(USE ADDITIONAL PAGES AS NECESSARY) 

AEROSPACE FORM 2380 

Air Force 

Mr. L. C. Block 

INSTRUCTIONS 

WHEN APPROVED BY GOVERN. 

MENT PROGRAM OFFICE, LINE 

OUT UNUSED SPACE TO PRE. 

CLUDE ADDITIONAL. ENTRIES. 
TO: Copyholder DATE 4 Nov 1965 

Aerospace TOR-669(6107-40)-1 

AEROSPACE CORPORATION 

DOCUMENT CHANGE NOTICE "1/1111/XIMI 

•NRO APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLASSIFIED 

SUBJECT Errata Pages FROM: Aerospace Publications 

Attached are revised pages to Aerospace TOR-669(6107-40)-1, "An Analysis of 

1•■ the Requirements for Very High Accuracy Image Motion Compensation, " dated 

October 1965. These pages should be inserted and supersede the pages revised, 

which should be removed and destroyed per applicable security regulations. 

Aerospace copyholders should DOCIN the revised pages (AS-65-0000-04815) into 

the above report (AS-65-0000-03578) per Company Practice 6-40-3. 

• 

71-(o 5"//.2 

Classification of this document 

will be downgraded to 

UNCLASSIFIED upon removal 

of Enclosures. 

GROUP-4 

Downgraded at 3-year intervals; 

declassified after 12 years. 

earaiMile AlG 

UNCLASSIFOED 

11111111111. 

RUTH ITY OF()-49-Ps\ 

DATE i31 

This document contains information affecting the national defense of the United States within the meaning of the Espionage Laws. Title 

18. U. S. C.. Section 793 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by law. 
UNCLASSIFIED 

0 

NRO APPROVED FOR 

RELEASE 1 JULY.2015 

Revised 4 Nov 1965 

UNCLASSIFIED 

D-8 

‘s,s 

't.st 

This document contains information affecting the nation a nse o i e `Stoles within the meaning of the Espionage Lows, Title 

18, U.S.C., Section 793 and 79A, the transmission or revelation of which in any manner to an unauthorized person is prohibited by low, 
OPTICAL 

I MC AXIS 

(IMAGE MOTION COMP.) 

SIDE OBLIQUE 

COMPENSATION 

TRANSLATIONAL 

LEAD SCREW 

D-18 

WIL4M12112tywo.- 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

UNCLASSIFIED 

e 

Revised 4 Nov 1965 

FLIGHT LINE 

Figure D-13. Film Transport System for Vertical or Side-Oblique 

Photography Employing a Drum-type Platen 

This document contains information affecting the notionol defense of the Untied Stoles within the meoning of the Espionage Lows, Title 

IN. U.S.C., Serlion 793 and 794, the foon,enist,ion or revelation of whi,h in any manner to on unouthorized person is prohibited by low. 
• NRO ARPROVED FOR 

RELEASE 1 JULY.2015 

UNCLASSIFIED 

FILM 

TAKE-UP 

FORWARD SIDE OBLIQUE (OR BACK S.0.) 

COMPENSATION ' 

OPTICAL AXIS 

TAKE-UP LOOPBEARINGS 

SUPPORT BELT 

IMAGE MOTION COMPENSATION 

/////v/////////// 

SIDE OBLIQUE 

COMPENSATION 

TRANSLATIONAL 

LEAD SCREW 

FLIGHT LINE 

Figure D-14. Schematic of Film Drive Employing Rotating ExposUre 

Slit Plate & Film Support Belt at Focal Plane 1.011111ft 

UNCLASSIIFI 

• 

This document contains information affecting the notional defense of the n a d es within the meaning of the Espionage lows, Title 

IA, U.S.C,, Section 793 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by 

Revised 4 Nov 1965 

D-19 
NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

UNCLASIKIED 

This document contains information affecting the notional defense of the United Slates within the meaning of the Espionage Lows, Title 

18, U.S.C., Section 793 and794, the tionsmission or revelation of which in any manner to on unauthorized person is prohibited by low. 

UNCLASSIrritu 

Revised 4 Nov 1965 

En 

tr) 

rd 

O 

O 

O 

0 

-641 

0) 

Aa 

u rxi 0 

cd 

0 

4-1 0 

tip fd 

IL) C

CI :44 

ct OD 

t) 

• 4-, 

0 r:4 

eg 

BOTTOM VIEW OF DRIVE 

CAMERA TRANSL ATION 

0 

LL 

FigureD- 15. 
FILM 

FILM SUPPLY 

TAKE-UP 

• BIRO APPROVED FOR 

RELEASE 1 JULY, 2015 

Revised 4 Nov 1965 

Uri !' 

Y AXIS 

TRANSLATION 

8 ROTATION 

Figure D-16. Schematic of Rotary Drum Film Drive Providing Freedom 

in Y Axis and Rotation above q, (0) 

UNCLASSIFIED 

1111PERIMI 

D - 22 

This document contnins information affecting the notional defense of the United States within the meaning of the Espionage laws, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in ony manner, to an unauthorized person is prohibited by low. 
OPTICAL 

I MC AXIS 

(IMAGE MOTION COMP.) 

SIDE OBLIQUE 

COMPENSATION 

TRANSLATIONAL 

LEAD SCREW 

: FLIGHT LINE 

UNCLASSIFIED 

. NIRO APPROVED FOR 

RELEASE 1 JULY 2015 

Revised 4 Nov 1965 

S. 

Figure D-19. Film Transport System for Vertical or Side-Oblique 

Photography Employing a Drum-type Platen 

UNCLASSIFIED D-28 

This document contains information affecting the notional defense o the

.,. 

within the meaning of the Espionage Laws, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to an unauthorized Person is prohibited by low. 
FILM 

TAKE-UP 

TAKE-UP LOOP 

BEARINGS 

SUPPORT BELT 

IMAGE MOTION COMPENSATION 

FORWARD SIDE OBLIQUE (OR BACK S.0.) 

COMPENSATION 

OPTICAL AXIS . 

/////AV/ ////J// 

SIDE OBLIQUE 

COMPENSATION 

TRANSLATIONAL 

LEAD SCREW 

FLIGHT LINE 

UNCLASSIFIED 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

Revised 4 Nov 1965 

Figure D-20. Schematic of Film Drive Employing Rotating Exposure 

Slit Plate & Film Support Belt at Focal Plane 

UNCLASSIFIED 

This document contains information affecting the national nse o 

n.

;thin the meaning of the Espionage Lows. Title 18, Section 793 and 794, the tionsinission or reve lotion of whi,h in any • manner to on unauthorized person is prohibited by low. 
UNC 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

• 

• 

• UNCLASSIFIED 

This document contoins information affecting the national defense of the United Stales within the meaning of the Espionage lows, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to on unauthorized person is prohibited by low. A 
UNCLASSIFIED op i4 c 5 

NRO APPROVED FOR 

RELEASE 1 JULY 2015 

Report No. 

TOR-269(A4126)-2 

Reissue A 

ERRATA SHEET 

This Errata Sheet applies to Report No. TOR-269(A4126)-2 

Reissue A entitled "Gemini Launch Vehicle Working Group, Launch 

Test Directive, Gemini Launch Vehicle-1 (AF SN 62-12556), " dated 

1 April 1964. The information contained herein is in accordance with 

Systems Test Objective Ammendment 3 dated 16 March 1964. Please 

make the following changes, in ink, to the subject report. 

Page 15, 1st col, item 7: change "+152.29" to "+153. 12". 

Page 16, 1st col, item 3: change "*331.43" to "+333.50". 

Page 16, 1st col, item 4: change "+333.43" to "+335.50". 

Page 16, 1st col, item 5: change "+353.43" to "+355.80". 

Page 19, Para B, under 

Minimum Ullage Volume, item 1: change "48.5" to "48.0". 

Page 19, Para B, under 

Minimum Ullage Volume, item 2: change "39.5" to "39.0", 

Page 20, Para C2. , line 3: 

Page 20, Para C2. , line 4: 

change line 3 to read: 

"Stage I start cartridge: 60°to 100° F". 

change line 4 to read: 

"Stage II start cartridge: 75°to 100° F". 

Delete: "(Ref waiver No. D45010 

to Stage II AGC spec. )" 

UNCLASSIFIED 

This document contains information affecting the national defense of the United States within the mooning of the Espionage Laws, Title 

18, U.S.C., Section 793 and 794, the transmission or revelation of which in any manner to an unauthorized person is prohibited by low.