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Sheet film camera movements
Large format sheet film cameras offer a range of movements - swings , tilts , and shifts of the lens relative to the film . These modify perspective , shape and depth of field in the image . The monorail camera is the most versatile . It uses movable units with locking screws , such as shown right , at the front and back of the camera . These control horizontal and vertical pivots , and sliding movements up , down , and sideways . With this arrangement camera movements are unlimited . The monorail camera should be used with a lens that has an extremely good covering power , as the camera movements often position it off - center to the film .
Sheet film camera unit
Using cross front movement
By shifting the lens panel to left or right you can take " square - on " pictures from slightly to one side of a subject . This is particularly useful when you want to avoid including the reflection of the camera in a mirror . The reflection- free version of the picture , above right , was taken with the camera moved right but the lens shifted left , so that it still framed and focused on the original subject , shown above left .
Principal camera movements
The movements of the front and back sections of a monorail camera can be divided into shifts -up and down , or sideways ; swings around a vertical axis ; and tilts on a horizontal axis . Shifts give the same effect as a shift lens on a 35 mm camera ( see p . 96 ) . By raising the front and / or lower- ing the back you can include more of the top and less of the bottom , without tilting the camera upward . As a result you can view upward , sideways , or downward , without making parallel lines in the subject appear to converge .
Swinging or tilting the back of the camera alters the appearance of shape in the image , as shown below . This allows you control over perspective . One or even two planes in pictures of cube shapes ( like buildings ) can be altered without disturbing the third . Back movements also help improve depth of field when the subject is principally on one oblique plane , as shown on the opposite page .
The main purpose of swinging or tilting the front of the camera is to improve depth of field by bringing the lens more closely into parallel with an oblique subject . Shift movement is also useful to avoid " vignetting " the subject unintentionally with , for example , the lens barrel itself .
Using back movements
All four pictures , right , were taken with the camera in exactly the same position . For the picture near right , top , the lens was square on to the camera back . In the picture . near right , bottom , the camera back was swung so as to shift the part of the focusing screen showing the right side of the box further from the lens . Linear perspective on the front of the box now con- verges toward the left instead of the right . For the pictures , far right , the camera back was swung and tilted , moving first the part of the screen showing the bottom left corner of the box away from the lens . top . Then the bottom right corner was pulled away from the lens , bottom . Double movements alter both the vertical and hori- zontal perspective of the box .
These pictures are extreme examples ; in most cases back movements are used for subtle control of image shape in still - life and architectural photography .
Maximizing depth of field
One of the most useful properties of front and back camera move- ments is the way you can use them to improve depth of field . The small picture , near right , was taken without camera movements Depth of field is shallow even at a small aperture - [ 11. You can correct this by tilting the camera lens forward and the back panel backward until imaginary lines through the subject plane , lens panel plane and focusing screen plane all converge to a single point , as shown below right . As in the picture , far right , the depth of field now extends throughout the whole subject plane , at the original aperture . You can use the same prin- ciple when photographing along an oblique vertical surface , using swing movements instead of tilts .
Types of film
Sheet films are available in many different specifications . Be careful to check what safelighting ( if any ) can be used in the darkroom . Notches in the edge of each sheet identify the film type . When you hold the film with the notch at the right - hand end of the top edge , the light - sensitive surface faces you .
Identifying sheet film
From front to back these films are , Kodak : Plus X ; Ektachrome day- light , and tungsten : Vericolor S.
Loading sheet film
1. Pull one of the plastic dark slides half out of the film holder The dark slide can remain in this position during loading and unloading .
2. Open the hinged end of the holder and switch off the white light . Unwrap the sheet film , remember to handle the film by its edges only .
3. Hold one sheet with the notch at top right . The emulsion side is now facing you when loaded . this side must face outward .
4. Load the sheet under the film holder guides . Push back the dark slide and close the holder . Turn the holder over and repeat with a second sheet of film .
Processing sheet film
1. Switch off white light and carefully remove the film from the film holder . Hold the film by its edges only .
2. Attach the film to a pro- cessing hanger by the four corner clips .
3. Place the hanger in a sheet film processing tank of developer . Agitate . Replace the lid and switch on the light .
4. Transfer the film to stop bath then fixer . Finally rinse in wetting agent and hang the washed film up to dry .
Sheet film camera movements
Large format sheet film cameras offer a range of movements - swings , tilts , and shifts of the lens relative to the film . These modify perspective , shape and depth of field in the image . The monorail camera is the most versatile . It uses movable units with locking screws , such as shown right , at the front and back of the camera . These control horizontal and vertical pivots , and sliding movements up , down , and sideways . With this arrangement camera movements are unlimited . The monorail camera should be used with a lens that has an extremely good covering power , as the camera movements often position it off - center to the film .
Sheet film camera unit
Using cross front movement
By shifting the lens panel to left or right you can take " square - on " pictures from slightly to one side of a subject . This is particularly useful when you want to avoid including the reflection of the camera in a mirror . The reflection- free version of the picture , above right , was taken with the camera moved right but the lens shifted left , so that it still framed and focused on the original subject , shown above left .
Principal camera movements
The movements of the front and back sections of a monorail camera can be divided into shifts -up and down , or sideways ; swings around a vertical axis ; and tilts on a horizontal axis . Shifts give the same effect as a shift lens on a 35 mm camera ( see p . 96 ) . By raising the front and / or lower- ing the back you can include more of the top and less of the bottom , without tilting the camera upward . As a result you can view upward , sideways , or downward , without making parallel lines in the subject appear to converge .
Swinging or tilting the back of the camera alters the appearance of shape in the image , as shown below . This allows you control over perspective . One or even two planes in pictures of cube shapes ( like buildings ) can be altered without disturbing the third . Back movements also help improve depth of field when the subject is principally on one oblique plane , as shown on the opposite page .
The main purpose of swinging or tilting the front of the camera is to improve depth of field by bringing the lens more closely into parallel with an oblique subject . Shift movement is also useful to avoid " vignetting " the subject unintentionally with , for example , the lens barrel itself .
Using back movements
All four pictures , right , were taken with the camera in exactly the same position . For the picture near right , top , the lens was square on to the camera back . In the picture . near right , bottom , the camera back was swung so as to shift the part of the focusing screen showing the right side of the box further from the lens . Linear perspective on the front of the box now con- verges toward the left instead of the right . For the pictures , far right , the camera back was swung and tilted , moving first the part of the screen showing the bottom left corner of the box away from the lens . top . Then the bottom right corner was pulled away from the lens , bottom . Double movements alter both the vertical and hori- zontal perspective of the box .
These pictures are extreme examples ; in most cases back movements are used for subtle control of image shape in still - life and architectural photography .
Maximizing depth of field
One of the most useful properties of front and back camera move- ments is the way you can use them to improve depth of field . The small picture , near right , was taken without camera movements Depth of field is shallow even at a small aperture - [ 11. You can correct this by tilting the camera lens forward and the back panel backward until imaginary lines through the subject plane , lens panel plane and focusing screen plane all converge to a single point , as shown below right . As in the picture , far right , the depth of field now extends throughout the whole subject plane , at the original aperture . You can use the same prin- ciple when photographing along an oblique vertical surface , using swing movements instead of tilts .
Types of film
Sheet films are available in many different specifications . Be careful to check what safelighting ( if any ) can be used in the darkroom . Notches in the edge of each sheet identify the film type . When you hold the film with the notch at the right - hand end of the top edge , the light - sensitive surface faces you .
Identifying sheet film
From front to back these films are , Kodak : Plus X ; Ektachrome day- light , and tungsten : Vericolor S.
Loading sheet film
1. Pull one of the plastic dark slides half out of the film holder The dark slide can remain in this position during loading and unloading .
2. Open the hinged end of the holder and switch off the white light . Unwrap the sheet film , remember to handle the film by its edges only .
3. Hold one sheet with the notch at top right . The emulsion side is now facing you when loaded . this side must face outward .
4. Load the sheet under the film holder guides . Push back the dark slide and close the holder . Turn the holder over and repeat with a second sheet of film .
Processing sheet film
1. Switch off white light and carefully remove the film from the film holder . Hold the film by its edges only .
2. Attach the film to a pro- cessing hanger by the four corner clips .
3. Place the hanger in a sheet film processing tank of developer . Agitate . Replace the lid and switch on the light .
4. Transfer the film to stop bath then fixer . Finally rinse in wetting agent and hang the washed film up to dry .
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