Editing View camera (section)

==Movements==<!-- This section is linked from [[Depth of field]] and intro -->
Photographers use view cameras to control [[Focus (optics)|focus]] and [[vanishing point|convergence of parallel lines]]. Image control is done by moving the front and/or rear standards. Movements are the ways the front and rear standards can move to alter perspective and focus. The term can also refer to the mechanisms on the standards that control their position.

Not all cameras have all movements available to both front and rear standards, and some cameras have more movements available than others. Some cameras have mechanisms that facilitate intricate movement combinations.

Some limited view camera–type movements are possible with [[SLR camera]]s using various [[tilt-shift lens|tilt/shift lenses]]. Also, as use of view cameras declines in favor of digital photography, these movements are simulated using computer software.<ref>[https://hcimage.com/assets/pdfs/HCImageGuide.pdf ''hcimage.com'']</ref><ref>{{cite web|url=http://files.ipevo.com/download/doc/p2v/P2V_UserManual_English_20120220.pdf |title=IPEVO Point 2 View User Manual |publisher=ipevo.com |date=2012-02-20 |access-date=2017-03-04}}</ref>
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===Rise and fall===

Rise and fall are the movements of either the front or rear standard vertically along a line in a plane parallel to the film (or sensor) plane. Rise is a very important movement especially in architectural photography.  Generally, the lens is moved vertically—either up or down—along the lens plane to change the portion of the image captured on the film. In the 35&nbsp;mm format, special [[Perspective control lens|shift lenses]] (sometimes called perspective control lenses) emulate the rise or fall of view cameras.

The main effect of rise is to eliminate converging parallels when photographing tall buildings. If a camera without movements is pointed at a tall building, the top is off. If the camera is tilted upwards to get it all in, the film plane is not parallel to the building, and the building seems narrower at the top than the bottom: lines that are parallel in the object converge in the image.

To avoid this apparent distortion, a wide-angle lens gets more of the building in, but includes more of the foreground and alters the perspective. A camera with rising front lets a normal lens be raised to include the top of the building without tilting the camera.

This requires that the [[image circle]] of the lens be larger than is required to cover the film without use of movements. If the lens can produce a circular image just large enough to cover the film, it can't cover the bottom of the film as it rises. Consequently, lens coverage must be larger to accommodate rise (and fall, tilt and shift).

In Figure a) below (images are upside down, as a photographer would see them on the ground glass of a view camera), the lens has been shifted down (fall). Notice that much of the unwanted foreground is included, but not the top of the tower.  In Figure b), the lens has been shifted up (rise): the top of the tower is now inside the area captured on film, at the sacrifice of unwanted green foreground.

{{multiple image
|direction=horizontal
|align=left
|header=
|footer=
|width1=174
|width2=180
|width3=180
|image1=rise.png
|alt1=Front standard rise
|caption1=Front standard rise
|image2=tower1.png
|alt2=Figure a) Fall
|caption2=Figure a) Fall
|image3=tower2.png
|alt3=Figure b) Rise
|caption3=Figure b) Rise
}}
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===Shift===
[[File:shift.png|frame|Front standard shift]]
Moving the front standard left or right from its normal position is called ''lens shift,'' or simply ''shift.'' This movement is similar to rise and fall, but moves the image horizontally rather than vertically. One use for shift is to remove the image of the camera from the final image when photographing a reflective surface.
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===Tilt===
[[File:Front Standard Tilt.png|frame|Front standard tilt]]
The axis of the lens is normally perpendicular to the film (or sensor). Changing the angle between axis and film by tilting the lens standard backwards or forwards is called ''lens tilt,'' or just ''tilt.'' Tilt is especially useful in [[landscape photography]]. By using the [[Scheimpflug principle]], the “plane of sharp focus” can be changed so that any plane can be brought into sharp focus. When the film plane and lens plane are parallel as is the case for most 35&nbsp;mm cameras, the plane of sharp focus is also parallel to these two planes. If, however, the lens plane is tilted with respect to the film plane, the plane of sharp focus is also tilted according to geometrical and optical properties. The three planes intersect in a line below the camera for downward lens tilt. The tilted plane of sharp focus is useful, in that this plane can be made to coincide with a near and far object. Thus, both near and far objects on the plane are in focus.

This effect is often incorrectly thought of as increasing the depth of field. Depth of field depends on the focal length, aperture, and subject distance. As long as the photographer wants sharpness in a plane that is parallel to the film, tilt is of no use. However, tilt has a strong effect on the depth of field by drastically altering its shape, making it asymmetrical. Without tilt, the limits of near and far acceptable focus are parallel to the plane of sharp focus as well as parallel to the film. With forward tilt, the plane of sharp focus tilts even more and the near and far limits of acceptable focus form a wedge shape (viewed from the side). Thus, the lens still sees a cone shaped portion of whatever is in front of it while the wedge of acceptable focus is now more closely aligned with this cone. Therefore, depending on the shape of the subject, a wider aperture can be used, lessening concerns about camera stability due to slow shutter speed and diffraction due to too-small aperture.

Tilting achieves the desired depth of field using the aperture at which the lens performs best. Too small an aperture risks losses to diffraction and camera/subject motion what is gained from depth of field. Only testing a given scene, or experience, shows whether tilting is better than leaving the standards neutral and relying on the aperture alone to achieve the desired depth of field. If the scene is sharp enough at f/32 with 2 degrees of tilt but would need f/64 with zero tilt, then tilt is the solution. If another scene would need f/45 with or without tilt, then nothing is gained. See Merklinger<ref>
Merklinger, H. M. (1996). ''Focusing the View Camera'', p.&nbsp;67. Bedford, Nova Scotia: Seaboard Printing Limited. {{ISBN|0-9695025-2-4}}. [http://www.trenholm.org/hmmerk/download.html  Available for download] (PDF). Page number refers to the electronic edition of 29&nbsp;December 2006.
</ref>
and Luong<ref>
Luong, Q. T. (2000). [http://www.largeformatphotography.info/how-to-focus.html How to Focus the View Camera]. On the Large Format Page. Retrieved 9&nbsp;July 2008.
</ref>
for extensive discussions on determining the optimal tilt (if any) in challenging situations.

With a forward tilt, the shape of the portion of a scene in acceptable focus is a wedge. Thus, the scene most likely to benefit from tilting is short in the front and expands to a greater height or thickness toward the horizon. A scene consisting of tall trees in the near, middle and far distance may not lend itself to tilting unless the photographer is willing to sacrifice either the top of the near trees and/or the bottom of the far trees.

Assuming lens axis front tilt, here are the trade offs in choosing between a small degree of tilt (say less than 3) and a larger tilt: A small tilt causes a wider or fatter wedge but one that is far off axis from the cone of light seen by the lens. Conversely, a large tilt (say 10 degrees) makes the wedge more aligned with the lens view, but with a narrower wedge. Thus, a modest tilt is often, or even usually, the best starting point.
Small and medium format cameras have fixed bodies that do not allow for misalignment of the film and lens planes, intentionally or not.  [[Tilt-and-shift lens|Tilt/shift]] (“TS”) or [[perspective control lens|perspective control]] (“PC”) lenses that provide limited movements for these cameras can be purchased from a number of lens makers.  High-quality TS or PC lenses are expensive. The price of a new Canon TS-E or Nikon PC-E lens is comparable to that of a good used large-format camera, which offers a much greater range of adjustment.
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===Swing===
[[File:swing.png|frame|Front standard swing (top view)]]
Altering the angle of the lens standard in relation to the film plane by swiveling it from side to side is called swing.  Swing is like tilt, but it changes the angle of the focal plane in the horizontal axis instead of the vertical axis. For example, swing can help achieve sharp focus along the entire length of a picket fence that is not parallel to the film plane.
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===Back tilt/swing===
Angular movements of the rear standard change the angle between the lens plane and the film plane just as front standard angular movements do. Though rear standard tilt changes the plane of sharp focus in the same manner as front standard tilt, this is not usually the reason to use rear tilt/swing. When a lens is a certain distance (its focal length) away from the film, distant objects, such as faraway mountains, are in focus. Moving the lens farther from the film brings closer objects into focus. Tilting or swinging the film plane puts one side of the film farther from the lens than the center is and the opposite point of the film is therefore closer to the lens.

One reason to swing or tilt the rear standard is to keep the film plane parallel to the face of the subject. Another reason to swing or tilt the rear standard is to control apparent convergence of lines when shooting subjects at an angle.

It is often incorrectly stated that rear movements can be used to change perspective.{{Citation needed|date=March 2013}} The only thing that truly controls perspective is the location of the camera in relation to the objects in the frame. Rear movements can let a photographer shoot a subject from a perspective that puts the camera at an angle to the subject, yet still achieves parallel lines. Thus, rear movements allow a change of perspective by allowing a different camera location, yet no view camera movement actually alters perspective.{{Citation needed|date=March 2013}}