Improvements in or connected with Photographic Cameras.
Year: 1899

page_text: Date of Application, 16th May, 1899
PROVISIONAL SPECIFICATION.
Improvements in or connected with Photographic Cameras.
We, ANNIBAL JEAN BAPTISTE LÉGÉ, of No. 31, Kirby Street, Hatton Garden,
in the County of London, Engineer, and WILLIAM HENRY ENGLAND, of No. 23,
Amesbury Avenue, Streatham Hill, in the County of Surrey, Photo-engraver,
do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in or connected with photographic
cameras to be employed in the production of colour records or photographs
according to the well known photochromoscope system.
In this class of camera, the sensitised plate or plates on which the chromo
gram sections are to be produced is or are arranged in a vertically moveable
frame with a colour screen opposite each sensitive plate or portion of a plate
upon which a chromogram section is to be produced and this frame is required
to be intermittently lowered so as to move into position each screen and the cor-
responding plate in successive order.
This movement has hitherto been effected either directly by hand or by means
of a clockwork motor which at predetermined intervals has released devices
retaining the frame, thus permitting or causing it to descend with a kind of
step by step motion into position in the required manner but this apparatus was
of an elaborate and expensive character and added materially to the cost of the
camera.
Now, one of the objects of the present invention is to obtain a simple and
inexpensive contrivance for effecting the same purpose in a more perfect manner.
In carrying this portion of the invention into effect, the sensitised plate or
plates within the ordinary dark slide and the colour screens are mounted opposite
each other in a frame or holder and this frame or holder is mounted with capa-
bility of vertically sliding in guides.
The frame is intended to fall by gravity but this movement might be assisted
by a spring and in order to regulate the descent of the frame in the desired
manner the frame is, at one side provided with recesses, teeth or projections located
at about midway of the height of the colour screens and plates, and in con-
nection with these recesses, teeth or projections is employed a spring detent
which is adapted to engage either of said recesses, teeth or projections, and hold
the frame with either of the colour screens and corresponding sensitive plate in
a proper position within the field of the lens.
In order to permit of the descent of the frame at the times desired, it is
necessary to withdraw the detent and this according to the present invention is
effected by any suitable means actuated by a pneumatic bulb but the following
arrangement of parts and which forms part of the present invention is preferred.
In connection with the detent is employed a cam wheel which carries or is
coupled with a ratchet wheel, and in connection with this ratchet wheel is
employed a driver actuated by a piston within a cylinder or by a like contrivance
and this cylinder is by a flexible tube connected with a pneumatic bulb so that
by squeezing the bulb the piston may be caused to rotate the cam wheel and

page_text: thus momentarily withdraw the detent from that recess, tooth or projection with
which it is for the time being engaged and permit the frame to descend so as to
bring a fresh colour screen and another portion of the sensitive plate into posi-
tion when the detent will come into engagement with the next recess, tooth or
projection of the descending screen and there retain it until the releasing device
is again operated in the manner hereinbefore described.
The pneumatic releasing device may if desired be also coupled with the lens
shutter so as to operate the same and in this case the ratchet wheel or driving
mechanism of the cam wheel is so arranged that two impulses of the pneumatic
bulb are required to bring one of the cams of the cam wheel into action so that
the first impulse will actuate the shutter of the lens to open the same and the
second impulse will close the said shutter and actuate the releasing mechanism
of the frame.
:
In order to prevent any detrimental shock on the falling of the frame, in
connection with the latter is employed an air or liquid cushion or brake which
consists of a tube or well containing the fluid and a plunger or piston which is
by a piston rod and offset from the frame connected therewith so that upon the
descent of the frame after having been released by the mechanism hereinbefore
described its descent will be regulated according to the diameter of the piston
with relation to the tube or well.
Or, instead of a solid piston, a trunk-like piston might be employed formed
with a perforation at the bottom capable of regulation by means of a screw or
the like so that the rate of admission of fluid to the trunk would regulate the
descent of the frame.
Or, a hollow floating piston or a permanent air or other cushion might be
employed and the frame provided with recesses or projections to receive an offset
or tooth from the piston rod and in this case the pneumatic releasing means
would be caused to move the offset or tooth out of engagement with the recess
or projection of the frame at the time that it withdrew the detent of the releas-
ing mechanism and in the fall of the frame the offset or tooth from the piston
rod would encounter the next recess or projection in order of the frame and the
piston would act as a brake or cushion to prevent the too sudden descent of
said frame.
i
The area of the colour screens employed in this class of photography is limited
owing to certain difficulties in producing the same and the use of sensitive
plates of approximately a larger area than the colour screens has been impossible.
Now, a further object of the present invention is to enable sensitive plates of
much larger area to be employed by which means improved photographic effects
may be obtained.
For this purpose, the frame holding the sensitive plates and colour screens
is widened so that whilst the sensitive plates retain their usual positions the
colour screens are placed some distance therefrom or immediately at the back
of the lens by which means a much larger field is covered by the rays passing
through the colour screen and a sensitive plate of a correspondingly larger area
can be employed.
It will be obvious that with this arrangement the sensitive plates and the
colour screens may be contained in one and the same frame or in separate frames
in which latter case the pneumatic releasing means and co-acting devices herein-
before described would be applied to each frame.
By the arrangement of parts herein before described, the means for operating
the screen frame are simplified and compacted and otherwise improved, whilst
the size of the photographs is capable of being increased to a considerable extent
with corresponding advantages.
1000
VAUGHAN & SON,
Agents for the Applicants,

page_text: Improvements in or connected with Photographic Cameras.
We, ANNIBAL JEAN BAPTISTE LÉGÉ, of No. 31, Kirby Street, Hatton Garden,
in the County of London, Engineer, and WILLIAM HENRY ENGLAND, of No. 23,
Amesbury Avenue, Streatham Hill, in the County of Surrey, Photo engraver,
do hereby declare the nature of this invention and in what manner the same is
to be performed to be particularly described and ascertained in and by the
following statement:-
Our said invention relates to improvements in or connected with photographic
cameras to be employed in the production of colour records or photographs
according to the well known photochromoscope system.
In this class of camera, the sensitised plate or plates on which the chromo-
gram sections are to be produced is or are arranged in a vertically moveable
frame with a colour sereen opposite each sensitive plate or portion of a plate
upon which a chromogram section is to be produced and this frame is required
to be intermittently lowered so as to move into position each screen and the cor-
responding plate in successive order.
This movement has hitherto been effected either directly by hand or by means
of a clockwork motor which at predetermined intervals has released devices
retaining the frame thus permitting or causing it to descend with a kind of
step by step motion into position in the required manner but this apparatus was
of an elaborate and expensive character and added materially to the cost of the
.camera.
Now, one of the objects of the present invention is to obtain a simple and
inexpensive contrivance for effecting the same purpose in a more perfect manner.
In carrying this portion of the invention into effect, the sensitised plate or
plates within the ordinary dark slide and the colour screens are mounted opposite
cach other in a frame or holder and this frame or holder is mounted with capa-
bility of vertically sliding in guides.
The frame is intended to fall by gravity but this movement might be assisted
by a spring and in order to regulate the descent of the frame in the desired
manner the frame is at one side provided with recesses, teeth or projections located
at about midway of the height of the colour screens and plates, and in con-
nection with these recesses, teeth or projections is employed a spring detent
which is adapted to engage either of said recesses, teeth or projections, and hold
the frame with either of the colour screens and corresponding sensitive plate in
a proper position within the field of the lens.
In order to permit of the descent of the frame at the times desired it is
necessary. to withdraw the detent and this according to the present invention is.
effected by any suitable means actuated by a pneumatic bulb but the following
arrangement of parts and which forms part of the present invention is preferred.
In connection with the detent is employed a cam wheel which carries or is
coupled with a ratchet wheel, and in connection with this ratchet wheel is
employed a driver actuated by a piston within a cylinder or by a like contrivance
and this cylinder is by a flexible tube connected with a pneumatic bulb so that
by squeezing the bulb the piston may be caused to rotate the cam wheel and
thus momentarily withdraw the detent from that recess, tooth or projection with
which it is for the time being engaged and permit the frame to descend so as to
bring a fresh colour screen and another portion of the sensitive plate into posi-
tion when the detent will come into engagement with the next recess, tooth or
projection of the descending screen and there retain it until the releasing device
is again operated in the manner hereinbefore described.

page_text: The pneumatic releasing device may if desired be also coupled with the lens
shutter so as to operate the same and in this case the ratchet wheel or driving
mechanism of the cam wheel is so arranged that three impulses of the pneumatic
bulb are required to bring one of the cams of the cam wheel into action so that
the first impulse will actuate the shutter of the lens to open the same and the
second impulse will close the said shutter and the third impulse will actuate the
releasing mechanism of the frame.
In order to prevent any detrimental shock on the falling of the frame, in
connection with the latter is employed an air or liquid cushion or brake which
consists of a tube or well containing the fluid and a plunger or piston which is
by a piston rod and offset from the frame connected therewith so that the
descent of the frame after having been released by the mechanism hereinbefore
described will be regulated according to the diameter of the piston with relation
to the tube or well.
Or, instead of a solid piston, a trunk-like piston might be employed formed
with a perforation at the bottom capable of regulation by means of a screw or
the like so that the rate of admission of fluid to the trunk would regulate the
descent of the frame.
Or, a hollow floating piston or a permanent air or other cushion might be
employed and the frame provided with recesses or projections to receive an offset
or tooth from the piston rod and in this case the pneumatic releasing means
would be caused to move the offset or tooth out of engagement with the recess
or projection of the frame at the time that it withdrew the detent of the releas-
ing mechanism and in the fall of the frame the offset or tooth from the piston
rod would encounter the next recess or projection in order of the frame and the
piston would act as as a brake or cushion to prevent the too sudden descent of
said frame.
The area of the colour screens employed in this class of photography is in
cameras as ordinarily constructed, limited owing to certain difficulties in pro-
ducing the same.
Now, a further object of the present invention is to facilitate the employment
of sensitive plates of large area by which means improved photographic effects
may be obtained.
For this purpose, the frame holding the sensitive plates and colour screens
is widened so that whilst the sensitive plates retain their usual positions the
colour screens are placed some distance therefrom or immediately at the back
of the lens by which means a much larger field is covered by the rays passing
through the colour screen and a sensitive plate of a correspondingly larger area
can be employed.
It will be obvious that with this arrangement the sensitive plates and the
colour screens may be contained in one and the same frame or in separate frames
in which latter case the pneumatic releasing means and co-acting devices herein-
before described would be applied to each frame.
And, in order that the said invention may be more clearly understood and
readily carried into effect, we will proceed, aided by the accompanying drawings,
more fully to describe the same.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a side elevation of a photographic camera constructed according
to the present invention the dark slide and colour screen frame being in their
midway position.
Figure 2 is a detail view of the pneumatic releasing device employed in
connection with the lens shutter.
Figure 3, is a rear elevation of the camera with parts broken away and the
dark slide removed. the colour screen frama haina
صيل

page_text: Figure 4, is a side elevation of the combined dark slide and colour screen
frame separate from the camera.
Figure 5, is an elevation of the pneumatic releasing mechanism of the colour
screen and dark slide.
Figure 6, is a side view thereof.
Figure 7, is an opposite edge view of part thereof.
Figure 8, is a sectional elevation showing a modified form of buffer or cushion
device for the screen frame and slide:
Figure 9 is a plan or top view of Figure 8.
Figure 10, is a side elevation of part of the camera representing a modified
form of buffer or cushion device.
Figure 11, is a side elevation with part broken away of a camera illustrating
the widened or extended frame arrangement of the colour screen and dark slide.
Figure 12, is a rear or side view of the front of the camera as constructed in
Figure 11, and connected parts separately.
Figure 13, is a side elevation of the dark slide portion of the extended frame
separately, and,
Figure 14, is a vertical section of the colour screen portion of the extended
frame separately.
In the several figures, in which like parts are indicated by similar letters of
reference, Figures 2 and 5, to 10, are drawn to an increased scale with respect
to the other figures of the drawings.
Referring to Figures 1, to 7, a represents the back of the camera, a¹ represents
the body or frame thereof which is removeably connected with the back a, in the
manner well known or a bellows connection might be employed between the
back and front as will be readily understood.
b represents the dark slide which is of ordinary construction and carries the
sensitive plates, in this example three, one above the other in the same vertical
plane, represents the usual shutters which are manipulated by hand, and c
represents the colour screen frame within which the colour screens c¹ are mounted
in similar positions opposite the sensitive plates and the colour screen frame c is
formed to receive the front edge of the dark slide which fits thereinto as shown
by the dotted lines in Figure 4, and is thus supported by a' projecting plate or
flange fixed to the underside of the colour screen frame c.
The colour screen frame c carrying the dark slide 6 is mounted with capability
of vertically sliding in guide grooves formed in the back a of the camera and
said frame c is intended to fall in the required manner by gravity but that
movement might be assisted by an arrangement of weights or springs as will
be readily understood but in order to regulate the descent of the frame c together
with the dark slide b in the desired manner, the colour screen frame c is at one
side thereof provided with studs, teeth or projections c³, or by modifying the
releasing mechanism recesses might be substituted therefor located at about mid-
way of the height of the colour screens c¹ and sensitive plates and in connection
with these studs, teeth or the like is employed a detent consisting of a stud
formed with a disc like base & carried by a spring arm & fixed with the side of
the back a of the camera.
The stud passes through and the disc fills so as to exclude light, an
aperture provided in the side of the back a of the camera and said stud is by the
spring caused to normally project into the path of the teeth or studs and is
thus adapted to engage either of said teeth studs or projections and hold the
colour screen frame c and dark slide 6 with either of the colour screens and cor-
responding sensitive plate in a proper position within the field of the lens.
In order to permit the descent of the colour screen frame e and dark slide b
at the times desired it is necessary to withdraw the detent 3 from that one of
the teeth or studs with which it is at the moment engaged and this according
to the present invention may be effected by any suitable means actuated by a

page_text: pneumatic bulb but the following arrangement of parts and which forms part of
the present invention is preferred.
In connection with the detent is employed a cam wheel e which acts upon
the free end of the spring arm & and the shaft or axis of this cam wheel is
carried at one end by a base plate or fitting f and at the other end by a cock or
bracket f therefrom and the cam wheel e carries or has formed therewith or is
coupled with or controlled by a ratchet wheel controlled by a check spring
and in connection with this ratchet wheel is employed a driver g² pivotally con-
nected with the lower end of a reciprocating cylinder and held to its work by
a spring and said cylinder works on a trunk or piston g fixed with the plate
or fitting and is normally held in its retracted position as shown in the draw-
ings by means of a coiled spring g' at one end fixed to the piston and at the
other end to the cylinder g.
The cylinder g or it might be any other suitable contrivance is by a flexible
tube connected with a pneumatic bulb y so that by squeezing the bulb g
the cylinder may through the driver and ratchet wheel be caused to rotate
the cam wheel e a portion of a revolution and thus through the spring arm d
momentarily withdraw the detent from that tooth or projection with which
it is for the time being engaged and permit the frame c to descend so as to bring
a fresh colour screen and another portion of the sensitive plate into position
when the detent will come into engagement with the next tooth or projec-
tion of the descending frame c and there retain it until the releasing device is
again operated in the manner herein before described.
At Figures 1 and 2, the pneumatic releasing apparatus is shown coupled by
means of a branch with the mechanism employed to actuate the shutter
of the lens h and which mechanism although inverted is substantially identical
with that hereinbefore described and is therefore similarly lettered but with the
following exceptions.
The ratchet wheel e³ has fixed therewith a mutilated wheel e provided with
two sets of teeth arranged at diametrically opposite points and the teeth of the
wheel e at the required times gear with the teeth of a mutilated wheel fixed
on the axis of the shutter which is closed by a spring in the usual way so
that in the normal position of the parts as indicated at Figure 1 the wheels e
and would be out of gear.
The cams or rises of the cam wheel e and the teeth of the mutilated wheel et
are so arranged that three impulses of the pneumatic bulb g are required to
bring one of the cams of the cam wheel e into action whilst the mutilated
wheel is arranged to come into action upon a single impulse and this first
impulse will bring one set of teeth of the mutilated wheel into gear with the
wheel and raise the lens shutter the second impulse will carry the engaging
set of teeth et beyond the teeth 2 thus causing the shutter to close and the
third impulse will actuate the cam wheel e and releasing mechanism of the
frame c thereby bringing a fresh set of plates within the field of the lens.
It will be obvious that other mechanical contrivances than those herein before
described may be employed for effecting the required movements upon the com-
pression of a pneumatic bulb.
In order to prevent any detrimental shock on the falling of the dark slide b
and colour screen frame c in connection with the latter is employed a cushion or
brake which in the example given at Figures 1 and 3, consists of a tube or
cylinder and a loosely fitting plunger or piston ¹ the rod of which is at its
upper end spread out and formed with an eye through which is loosely passed
a stud which works in a slot a² in the back of the camera and at its outer
end is provided with a milled head and at the inner end threaded or otherwise
formed to engage a corresponding hole formed in the side of the frame c
Upon the descent of the frame c after having been released by the mechanism
herein before described the air beneath the piston will form a cushion and will
gradually escape past the piston and thus the descent of the frame c and dark

page_text: slide will be regulated according to the diameter of the piston with relation
to the cylinder i.
.
It will be understood that in lieu of air a suitable liquid such as glycerine may
be employed in the evlinder provided the proportion of the diameter of the
piston to that of the cylinder is suitably modified.
In the example given at Figures 8 and 9, a modified form of cushion device is
illustrated and which is somewhat similar to that lastly hereinbefore described
but in this case the piston more closely fits the cylinder i and the piston rod
is at its lower end formed with an air way and outlet * therethrough_and
the area of which air way is capable of being regulated by a screw stud or
valve 2³.
In the example given at Figure 10, a further modification is shown in which
a coiled spring or it might be an air bag is enclosed in a cylinder or case i
and supports the piston with a resistance or spring pressure capable of being
to some extent regulated by a moveable abutment or platform actuated by a
set screw '.
In this case, instead of the piston rod having a fixed relation to the frame c
when in action said piston rod is independent thereof and at its upper end is
shaped to form a buffer to engage in turn each of a series of studs et correspond-
ing with the studs and the stud e of the frame e falling upon the piston rod
more or less compresses the spring * until the frame e assumes the required
position.
+
Upon the next movement of the releasing mechanism of the frame e the
spring arm which is formed with an offset 'overlapping the piston rod 2
imparts to said piston rod (which possesses the required flexibility) a slight
lateral movement sufficient to disengage it. from the stud which is at the
moment resting thereon and upon the spring arm returning to its normal
position which it does instantaneously the piston rod will catch the descending
sind next in order.
In the example given at Figures 11 to 14, a widened or extended form of
colour screen frame is illustrated.
The area of the colour screens employed in this class of photography. is ordi-
narily limited owing to certain difficulties in producing the same and the use of
sensitive plates of approximately a larger area than the colour screens has been
impossible, with cameras as ordinarily constructed.
Now, a further object of the present invention is to facilitate the employment
of sensitive plates of much larger area than the colour screens by which means
improved photographic effects may be obtained.
For this purpose, the frame connecting the colour screens and sensitive plates
is widened or extended so that whilst the dark slide b containing the sensitive
plates retains its usual position in the back of the camera the colour screen
frame is placed some distance therefrom in the front a¹ of the camera.
C
The means emploved for effecting this object may vary considerably but the
arrangement of parts represented in the drawings is as follows:-
The dark side is removeably supported in a frame * mounted with capa-
bility of vertically sliding in grooves in the back and said frame * is actuated
and controlled by the same mechanism as hereinbefore described with respect
to the first arrangement.
The frame at suitable positions is by telescopic rods 2 connected so as to
move in unison with the colour screen frame c which slides vertically in guides
formed in the front of the camera and the frame e at its upper and lower
ends is connected in the front by means of short lengths of flexible or bellows
material the office of which is to prevent the passage of light past the ends of
said frame and the back and front are connected by a bellows or it might
be a telescopic body a³.
"
The colour screens in the frame e and sensitive plates in the dark slide b

page_text: are so arranged that the centre of each colour screen c¹ coincides with the centre
of the corresponding sensitive plate.
It will be obvious that instead of carrying the sensitive plates and colour
screens in one connected frame, the frame * carrying the dark slide and the
frame carrying the colour screens may slide independently in the guides in the
back and front a¹ of the camera in which case each frame would require to be
fitted with releasing and controlling mechanism similar to that described with
respect to Figure 1 said mechanism being similarly coupled up to one pneumatic
bulb.
By the arrangement of parts herein before described, the means for operating
the slide and screen frame are simplified and compacted and otherwise improved
whilst the size of the photographs is capable of being increased to a considerable
extent with corresponding advantages.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is:-
1. A photographic camera comprising a hack, a body or front, a lens carried
carried by the front, a dark slide or frame vertically moveable in guides in the
back and carrying a sensitive plate or several sensitive plates in vertical align-
ment, means for holding the slide in either of the positions required to expose
a plate or a portion of a plate and a pneumatic device for releasing the slide
from said holding means and permitting a fresh plate or portion of a plate to
descend into the field of the lens, substantially as herein shown and described
and for the purpose stated.
2. A photographic camera comprising a back, a body or front, lens carried by
the front, a frame vertically moveable in guides in the back and carrying several
colour screens in vertical alignment a dark slide carried by said frame in the rear
thereof, means for holding one or several sensitive plates in the dark slide in
positions opposite the colour screens, means for holding the frame in either of the
positions required to expose a plate and a pneumatic device for releasing the
frame from said holding means and permitting a fresh screen and plate or a
portion of a plate to descend into the field of the lens, substantially as herein
shown and described, and for the purpose stated.
3. A photographic camera comprising a back, a body or front; a lens carried
by the front, a slide or frame vertically moveable in guides on the back and
carrying a sensitive plate or several sensitive plates in vertical alignment, means
for holding the dark slide in either of the positions required to expose a plate
or portion of a plate, a pneumatic device for releasing the slide from said holding
means and permitting a fresh plate or portion of a plate to descend into the
field of the lens and a buffer arrangement for preventing the too sudden descent
of said slide, substantially as herein shown and described and for the purpose
stated.
4. A photographic camera comprising a back, a body or front, a lens carried
by the front, a dark slide or frame vertically moveable in guides in the back
and carrying a sensitive plate or several sensitive plates in vertical alignment;
means for holding the slide in either of the positons required to expose a plate
or a portion of a plate, means for opening and closing the lens shutter and a
pneumatic device coupled with the means for releasing the slide and the means
for actuating the lens shutter, said releasing and actuating means being 80
arranged that the first impulse or impulses will actuate the lens shutter and the
following impulse or impulses will operate the releasing means, substantially
as herein shown and described and for the purpose stated.
5. A photographic camera comprising a back, a body or front, a lens carried
by the front, a slide or frame vertically moveable in guides in the back and
carrving the necessary plate or plates and screens, several studs or projections
or their equivalents carried by the frame or slide and arranged at suitable dis.

page_text: tances apart, a detent extending through the back in the path of the studs so
as to engage the same, a spring arm carrying said detents and at its end engaging
a cam wheel, a ratchet wheel fixed with the cam wheel, an air cylinder furnished
with a driver for rotating the ratchet wheel and cam wheel, a pneumatic bulb
connected with the air cylinder so that by squeezing the bulb the detent will
be retracted and the frame or slide caused to descend and a buffer arrangement
coupled with the frame or slide for preventing the too sudden descent thereof,
substantially as herein shown and described and for the purpose stated.
6. A photographic camera comprising a back, a body or front, a lens carried
by the front, a slide or franie vertically.moveable in guides in the back and carry-
ing the necessary plate or plates and screens, two rows of studs or projections or
their equivalents carried by the frame or slide and arranged at suitable distances
apart, a detent extending through the back into the path of one row of studs so
as to engage the same, a spring arm carrying said detent and at its end engaging
a cam wheel, a ratchet wheel fixed with the cam wheel, an air cylinder pro-
vided with a driver for rotating the ratchet wheel and cam wheel, a pneumatic
bulb connected with the air cylinder so that by squeezing the bulb the detent
will be retracted and the frame or slide caused to descend, an adjustable spring or
other cushion or buffer supporting a piston or plunger, a rod extending upward
from the piston and projecting into the path of the second row of studs of the
frame or slide and adapted to catch the same in its descent and an offset from the
spring arm of the detent adapted to laterally move the piston rod of the buffer
out of engagement with the second row of studs of the frame, substantially
as herein shown and described and for the purpose stated.
7. A photographic camera comprising a back, a front, a bellows or like body,
a lens carried by the front, a dark slide vertically moveable in guides in the
back and carrying a sensitive plate or several sensitive plates in vertical align-
ment, means for holding the dark slide in either of the nositions required to
expose a plate or a portion of a plate, a frame vertically moveable in guides in
the front of the camera or in other position near to the lens and at a distance.
from the dark slide and carrying colour screens arranged opposite the sensitive
plate or plates said frame being widened or extended and connected with the
dark slide by means of telescopic bars or otherwise so as to move in unison there-
with, a pneumatic device for releasing the dark slide from the holding means
and permitting a fresh plate or portion of a plate and colour screen to descend
into the field of the lens and a buffer arrangement for preventing the too sudden
descent of the slide and frame, substantially as herein shown and described and
for the purpose stated.
8. A photographic camera comprising a back, a front, a hellows or like body,
a lens carried by the front, a dark slide vertically moveable in guides in the
back and carrying a sensitive plate or several sensitive plates in vertical align-
ment, an independent frame, vertically moveable in guides in the front of the
camera, or in other position near to the lens and at a distance from the dark
slide and carrying colour screens arranged opposite the sensitive plate or plates.
independent means for holding the dark slide and frame in either of the posi-
tions required to expose the plates, or portions of the plate, pneumatic devices
for releasing said slide and frame from the holding means said devices being if
desired coupled and buffer arrangements for preventing the too sudden descent
of the slide and frame, substantially as herein shown and described and for the
purpose stated.