Video camera adaptor for film cameras

An adaptor affixing a video camera to a film camera. The adaptor permits the transmission of the image formed on the focusing screen of the latter to reach the former in a correct left-right and up-down orientation. For this purpose, it utilizes a mirror which, in one position, transmits the image to the video camera. In the other, it permits the viewing of the image on the film camera's focusing screen with or without magnification. Nonetheless, it permits visual and manual access to the normal controls of the camera. A shield prevents the access of light not from the film camera's image to the video camera for a sharper and clearer image. The adaptor attaches to the usual coupling devices of the film camera which generally permits the affixing of photographic accessories. To permit a more compact system, the adaptor bends the light path from the image screen to the video camera through an angle greater than 90 degrees but not greater than 180 degrees. For a single lens reflex camera, this angle may amount to 130 degrees. For a view camera, the light path bends 180 degrees.

BACKGROUND 
The combination of a video camera with a film camera portends several 
advantages. Initially, it allows the photographer, by looking at the video 
monitor, to arrange his scene without the necessity of regularly and 
frequently returning to the film camera itself. Simply looking at the 
monitor will tell him how the final picture will most likely appear. 
Further, the video camera may have the ability to capture the actual 
pictures taken by a film camera. The photographer or the subject of the 
pictures may then view the magnetically recorded scenes on the video 
monitor to determine if they prove satisfactory. If not, the subjects may 
undergo further photographing without waiting for the development of the 
film itself and the necessity for returning to the photographer. 
One system finding use attempts to accomplish this objective by placing a 
video camera with a beam splitter in front of the camera lens. As a 
consequence, it renders the video camera independent of the camera's 
optics. Thus, the photographer does not have the opportunity to view the 
film camera's focus since the picture he sees on the monitor does not pass 
through the camera's lens. 
Further, the diversion of a portion of the beam reduces the amount of light 
available for the film camera. That has all of the usual photographic 
deleterious consequences. 
Further, the film camera may likely employ different lenses. As a result, 
the system may not even provide on the video monitor the correct size 
picture that the film camera will see. 
Further, this type of system makes impossible use of the front projection 
system, which places a picture behind the photographed subject. 
Accordingly, this type of system does not accomplish the desire for the 
effective video monitoring of what a film camera actually experiences. 
Another concept employs a unified, integrated system employing a film 
camera with an integrated video camera. This system does permit the 
observing of the results produced by the camera's own lens. 
However, as an integrated system, it eliminates the photographer's choice 
of actual equipment he may wish to use for the film camera. Furthermore, 
it deprives him of any opportunity to actually view the film camera's 
focusing screen to make sure that he has achieved the best picture 
possible. Additionally, it limits the utility of the film camera except 
for the specific purpose of utilization with the video camera. 
Other systems utilizing large bulky adaptors have also found use. However, 
they have such a size as to limit their overall utility. Moreover, they 
often have the result of precluding the viewing and manipulation of the 
camera's controls. 
Accordingly, the search continues for a system that will attach a video 
camera to a general film camera. It should allow the utilization of a 
video camera when desired with access to the film camera's controls. 
SUMMARY 
A video adaptor for a film camera which, by its lens, creates an image in a 
substantial plane first includes adaptor means for, when in a particular 
position relative to the plane of the image, transmitting that image to a 
video camera. The adaptor means itself includes optics means for 
transmitting the image along a path to a particular location relative to 
but removed from the camera's image plane. It further has a shielding 
device, coupled to the optics means, to exclude light not originating from 
the image itself from the location to where the image is transmitted. 
Furthermore, the video adaptor includes a holding device which couples to 
the adaptor means. It affixes the adaptor means to the film camera in the 
particular position in which it can transmit the image. The holding device 
permits the manual releasing of the adaptor means from the film camera. 
Thus, they may disengage from each other so that the film camera may find 
its normal use. 
Instead of including a shielding device, the video adaptor will find use 
where the film camera has controls as well as its lens. The holding device 
should then permit the visual and manual access to these controls of the 
film camera. 
As a separate and independent aspect, the video adaptor may have a viewing 
device coupled to the adaptor means and possessing two configurations. In 
the first configuration, the viewing device directs the image from the 
image plane to the video camera. In the second of the two configurations, 
the viewing device directs the image to a location viewable by the 
photographer. The viewing device may undergo manual switching between 
these two configurations so that the photographer may choose whether to 
view the image on the camera's focusing screen or to send it to the video 
camera. 
The method of using the adaptor involves transmitting an image formed in a 
substantial plane by the lens of a film camera. It begins with placing an 
adaptor means in a particular position relative to the image plane. The 
method next involves releasably affixing the adaptor to the film camera 
with the adaptor means in the particular position. An image is next 
transmitted from the image plane through optics means forming part of the 
adaptor means to the lens of a video camera. The method concludes with 
shielding light from the lens of the video camera. 
As an alternative to shielding light from the lens of the video camera, the 
method may involve the utilization of a film camera having controls. In 
this instance, a further step in the process involves, with the adaptor 
means affixed to the film camera, viewing and manipulating the film 
camera's controls. 
As a further aspect, the method may involve divertingthe image transmitted 
from the image plane of the camera to a location separate from the video 
camera. There it may be directly viewed by the human eye. Subsequently, 
the image returns to the video camera for its subsequent use there.

DETAILED DESCRIPTION 
FIG. 1 shows a medium format camera generally at 20 with its lens 21 and 
sitting on the tripod 22. The video adaptor shown generally at 23 
transmits the image formed on the focusing plane of the camera 20, as 
discussed below, to the video camera 24. 
The adaptor 23 includes the main section 26 and the side shaft 27. As seen 
in FIG. 5, the side shaft 27 basically holds the lens 28 of the video 
camera in place where it may receive the image from the film camera. The 
housing 29 of the side shaft 27 excludes exterior light from the video 
camera's lens 28. 
As seen in FIGS. 4 and 5, the image from the film camera 20 passes through 
the opening 29 of the main housing 26. It then strikes the mirror 30 which 
transmits it directly into the video camera lens 28. The screws 31 hold 
the mirror 30 to the plate 32, which in turn attaches to the shaft 33. 
In FIG. 11, the original image 35 would strike the film plane 36 of the 
camera 20 with reversed left-right and up-down orientation. For the camera 
20 to take an actual picture, its mirror 37 pivots downward to allow the 
image to pass through to the film plane 36. 
When not taking a picture, the mirror 37 pivots to its upright position as 
shown in FIG. 11 to give an image on the camera's focusing screen 38 that 
has correct up-down orientation but a reversed left-right appearance. The 
image from the camera's focusing screen 38 then hits the adaptor's mirror 
30 which serves to again reverse the left-right orientation so that image 
striking the video camera's lens 28 has both correct left-right and 
up-down orientation. 
As discussed above and as seen in FIG. 5, in particular, the mirror 30 may 
occupy two positions. In its upper position, seen in solid lines in that 
figure, it casts the image from the focusing screen 38 of the camera 20 
onto the video camera lens 28. 
However, the knob 39 connects through the shaft 33 to the plate 32 and also 
the mirror 30. It can rotate the mirror 30 downward to its alternate 
position shown in phantom in FIG. 5. To keep the mirror 30 in the correct 
position, the magnet 40 passes through and attaches to the plate 32, and 
extends beyond either side of the plate 32 as seen in FIGS. 5 and 6. The 
magnet 40 keeps the mirror in its upper position by adhering to the small 
steel block 41 held to the side of the main adaptor unit 26 by the screw 
42. 
In its lower configuration, the magnet 40 sticks to the lower steel block 
43 held to the side of the main adaptor unit 26 by the screw 44. The 
operator changes the position of the mirror 30 by rotating the knob 39 
with sufficient force to overcome the attraction between the magnet 40 and 
the upper or lower steel block 41 or 43 as appropriate. 
The position of the knob 39, when it moves the mirror down to its lower 
position also appears in phantom in FIG. 5. In this configuration, the 
mirror 30 can no longer deflect the image passing through the opening 29 
onto the video camera's lens 28. Instead, it passes to the opening 45 
where the photographer may visually and directly view it. The magnifier 46 
permits a detailed examination of the image as it appears on the focusing 
screen 38 of the camera 20. The steel screw 47 attracts a magnet on the 
side of the magnifier 46 to keep it properly positioned when placed in the 
viewing path. 
Alternately, the photographer may wish to view the image on the focusing 
screen 38 without the aid of the magnifier 46. In this instance, he simply 
rotates it out of place, as shown in phantom in FIG. 5. With the mirror 30 
in its downward position as shown in phantom he may then merely look 
through the opening 45 to see the image produced by the film camera lens 
21 on its focusing screen. 
As seen in FIGS. 5 and 6, the coil spring 49 under compression surrounds 
the shaft 33 which in turns connects to the knob 39. It biases the shaft 
33, the plate 32, and the mirror in the direction away from the side of 
the main adaptor section 26 through which the shaft 33 attaches to the 
knob 39. 
Also as seen in particular, in FIGS. 1, 2, 5, and 11, the adaptor 23, 
particularly its mirror 30, bends the path of the image through the angle 
51 (as seen in FIG. 5) of 130 degrees. In the single lens reflex camera 
20, this provides for a compact overall structure. In this fashion, the 
adaptor 23 with the video camera 24 provides minimal encumbrance to the 
use of the camera 20. The use of the adaptor 23 still permits the viewing 
of and access to all of the usual controls of the camera 20. 
To achieve a compact structure, the adaptor should generally bend the path 
of the light travelling from the film camera's focusing screen to the 
video camera through an angle greater than 90 degrees and less than or 
equal to 180 degrees. As discussed below with regards to FIG. 12, the view 
camera shown there bends the light path through two 90 degree angles for a 
total of 180 degrees of deflection. 
As seen in FIGS. 7 to 10, the film camera 20 includes the recessed slot 55 
on one side of its focusing screen and the upstanding screw 56 on the 
other side. These permit the attachment of accessories in the vicinity of 
the focusing screen 38 itself. The adaptor 23 takes advantage of these 
components to attach itself to the camera 20. 
As shown in FIG. 7, the attachment of the adaptor 23 commences by the 
photographer placing the adaptor 23 above and, as seen in that FIGURE, to 
the left of the focusing screen 38 of the camera 20. This allows the 
downward movement of the adaptor 23 toward the camera to result in the 
arrangement seen in FIG. 9. In particular, the lateral displacement of the 
adaptor 23 from the focusing screen 38 allows the downward movement of the 
former without the washer 57 held in place by the screw 58 making contact 
with the ridge 59 in which appears the slotted recessed 55. Similarly, the 
lateral displacement of the adaptor 23 allows its downward motion without 
interference from the screw 56. 
Moving the adaptor 23 to the right in FIG. 9 relative to the camera 20 
allows for the attachment of the former to the latter. This occurs because 
the washer 57 fits into the recessed slot 55 in the ridge 59 of the camera 
20. 
At the same time, the left side of the adaptor 23 includes the 
mushroom-shaped opening 62 (seen from the side in FIG. 8). As the adaptor 
23 moves to the right in FIG. 9, the screw 56 fits into the 
mushroom-shaped opening 62. At the furthest right movement of the adaptor 
23, the screw 56 sits totally embedded in the opening 62 as seen in FIGS. 
10 and 2. At this stage, the adaptor 23 cannot move to the right because 
it abuts the ridge 59 of the camera 20. Furthermore, it cannot move upward 
since the washer 57 fits in the recessed slotted 55 and the screw 56 fits 
in the opening 62. 
As a consequence, the only motion permitted of the adaptor 23, at this 
point, would be a lateral displacement to the left, reversing the motion 
which brought the two components together in FIG. 10. To prevent that 
motion, the angle rod 63 moves forward in FIGS. 7, 9, and 10 (and the 
right in FIG. 8). This causes the angle rod 63 to move through the opening 
62 in a direction perpendicular to the length of the screw 56. With the 
rod 62 in place, the screw 56 abuts against it to prevent motion of the 
adaptor 23 to the left in FIG. 10. The entire angle rod 63 appears in FIG. 
4 with a portion also seen in FIG. 3 to show that it extends beyond the 
edge of the adaptor 23. Thus, the photographer may easily insert and 
remove it to allow for the attachment and removal of the adaptor 23 from 
the camera 20. 
The view camera indicated generally at 71 in FIG. 12 includes the lens 72 
which sits in the bracket 73 moving along the track 74. The bellows 75, in 
the typical fashion, allows the movement of the lens 72 to the left and 
right in FIG. 12 for focusing. The video adaptor indicated generally at 78 
attaches to the rear 79 of the camera 71. It may do so using the usual 
accessory coupling devices generally found on the view camera. The adaptor 
serves to attach the video camera 80 to the view camera 71. 
The two mirrors 81 and 82 take the image formed on the focusing screen 83 
of the view camera 71 and deflects it through two 90 degree angles to 
provide it to the video camera 80. Thus, the total deflection of the path 
of the image from the focusing screen 83 to the video camera 80 amounts to 
180 degrees. 
As seen in FIG. 12, the photographer may rotate the lower mirror 81 in the 
counter-clockwise direction until it reaches the position shown in phantom 
in FIG. 12. This permits the photographer to directly view the image on 
the focusing screen 83 of the view camera 71 through the resulting opening 
85 in the adaptor 78.