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A view camera is a large format camera in which the lens forms an erect image on a ground glass screen directly at the film plane. The image is viewed, composed, and focused, then the glass screen is replaced with the film to expose exactly the same image seen on the screen.
This type of camera was developed during the era of the daguerreotypeStroebel, L. D. (1986). View Camera Technique, 5th ed., p. 212. Boston: Focal Press. (1840s–1850s) and is still in use, some using drive mechanisms for movement (rather than loosen-move-tighten), more scale markings, and/or more spirit levels. It comprises a flexible bellows that forms a light-tight seal between two adjustable standards, one of which holds a lens, and the other a ground glass or a photographic film holder or a digital back.Stroebel (1986). p. 2. There are three general types: the rail camera, the field camera, and those that don't fit into the other categories.
The bellows is a flexible, accordion-pleated box. It encloses the space between the lens and film, and flexes to accommodate the movements of the standards.Adams, A. (1980). The Camera. Boston: Little, Brown and Company. The front standard is a frame that holds the lensboard, to which the lens (perhaps with shutter) is attached.
At the other end of the bellows, the rear standard is a frame that holds a ground glass plate, used for focusing and composing the image before exposure—and is replaced by a holder containing the light-sensitive film, plate, or image sensor for exposure. The front and rear standards can move relative to each other, unlike most other camera types. Whereas most cameras control only the distance of the plane of focus from the camera, the view camera can also adjust the orientation of the plane of focus, and perspective control. The camera is normally used on a tripod support.
View cameras use large format sheet film—one sheet per photograph. Standard sizes in inches are: 4×5, 5×7, 4×10, 5×12, 8×10, 11×14, 7×17, 8×20, 12×20, 20×24, and larger for process cameras. (It is usual to list the short side first in the Americas, and the long side in many other countries, thus 4×5 is the same as 5×4). A similar, but not identical, range of Metric system sizes is used in many countries; thus 9×12 cm is similar to, but not interchangeable with, 4×5 inches and 13×18 cm is similar to, but not interchangeable with, 5×7 inches. The most widely used format is 4×5, followed by 8×10.
A few rollfilm cameras have movements that make them as versatile as a sheet film view camera. Rollfilm and instant film backs are available to use in place of a sheetfilm holder on a single-film camera.
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 using various tilt-shift lens. Also, as use of view cameras declines in favor of digital photography, these movements are simulated using computer software. hcimage.com
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.
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 Merklinger, H. M. (1996). Focusing the View Camera, p. 67. Bedford, Nova Scotia: Seaboard Printing Limited. . Available for download (PDF). Page number refers to the electronic edition of 29 December 2006. and Luong Luong, Q. T. (2000). How to Focus the View Camera. On the Large Format Page. Retrieved 9 July 2008. 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/shift (“TS”) or 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.
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. 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.
Almost any lens of the appropriate coverage area may be used with almost any view camera. All that is required is that the lens be mounted on a lensboard compatible with the camera. Not all lensboards work with all models of view camera, though different cameras may be designed to work with a common lensboard type. Lensboards usually come with a hole sized according to the shutter size, often called the Copal Number. Copal is the most popular maker of for view camera lenses.
The lens is designed to split into two pieces, the front and rear elements screwed, usually by a trained technician, into the front and back of the shutter assembly, and the whole fitted in a lensboard.
View camera lenses are designed with both focal length and coverage in mind. A 300 mm lens may give a different angle of view (either over 31° or over 57°), depending on whether it was designed to cover a 4×5 or 8×10 image area. Most lenses are designed to cover more than just the image area to accommodate camera movements.
Focusing involves moving the entire front standard with the lens assembly closer to or further away from the rear standard, unlike many lenses on smaller cameras in which one group of lens elements is fixed and another moves.
Very long focus lenses may require that the camera be fitted with special extra-long rails and bellows. Very short focal length wide-angle lenses may require that the standards be closer together than a normal concertina-folded bellows allows. Such a situation requires a bag bellows, a simple light-tight flexible bag. Recessed lensboards are also sometimes used to get the rear element of a wide angle lens close enough to the film plane; they may also be of use with , since these compressed long-focus lenses may also have very small spacing between the back of the lens and the film plane.
are not used in view camera photography, as there is no need for rapid and continuous change of focal length with static subjects, and the price, size, weight, and complexity would be excessive. Some lenses are "convertible lens": the front or rear element only, or both elements, may be used, giving three different focal lengths, though the quality of the single elements is not as good at larger apertures as the combination. These are popular with field photographers who can save weight by carrying one convertible lens rather than two or three lenses of different focal lengths.
Soft focus lenses introduce spherical aberration deliberately into the optical formula for an effect considered pleasing, and flattering to subjects with less than perfect complexions. The degree of soft-focus effect is determined by either aperture size or special disks that fit into the lens to modify the aperture shape. Some antique lenses, and some modern SLR soft focus lenses, provide a lever that controls the softening effect by altering the optical formula.
With an inexpensive modification of the darkslide, and no modification to the camera, half a sheet of film can be exposed at a time. While this technique could be used for economy where a larger image is not required, it is almost always used with the intention of obtaining a panoramic format so that, for example, a 4×5 camera can take two 2×5 photos, an 8×10 can take two 4×10s etc. This is popular for landscape photography, and in the past was common for group photographs (hence, half-frame panorama formats such as 4x10 are commonly referred to as "Banquet formats")
Digital camera backs are available for view cameras to create instead of using film. Prices are high compared to smaller .
To operate the view camera, the photographer opens the shutter on the lens to focus and compose the image on a ground glass plate on the rear standard. The rear standard holds the ground glass in the same plane that the film later occupies—so that an image focused on the ground glass is focused on the film. The ground glass image can be somewhat dim and difficult to view in bright light. Photographers often use a focusing cloth or "dark cloth" over their heads and the rear of the camera. The dark cloth shrouds the viewing area and keeps environmental light from obscuring the image. In the dark space created by the dark cloth, the image appears as bright as it can, so the photographer can view, focus, and compose the image. Often, a photographer uses a magnifying lens, usually a high quality loupe, to critically focus the image. An addition over the ground glass called a Fresnel lens can considerably brighten the ground glass image (with a slight loss of focusing accuracy). The taking lens may be stopped down to help gauge depth of field effects and vignetting, but the photographer generally opens the lens to its widest setting for focusing.
The ground glass and frame assembly, known as the spring back, is held in place by springs that pull and hold the ground glass firmly into the plane of focus during the focusing and composition process. Once focusing is complete, the same springs act as a flexible clamping mechanism to press the film holder into the same plane of focus that the ground glass occupied.
To take the photograph, the photographer pulls back the ground glass and slides the film holder into its place. The shutter is then closed and cocked, the shutter speed and aperture set. The photographer removes the darkslide that covers the sheet of film in the film holder, and triggers the shutter to make the exposure. Finally, the photographer replaces the darkslide and removes the film holder with the exposed film.
Sheet are generally interchangeable between various brands and models of view cameras, adhering to de facto standards. The largest cameras and more uncommon formats are less standardized.
Special film holders and accessories can fit in place of standard film holders for specific purposes. A Grafmatic, for example, can fit six sheets of film in the space of an ordinary two-sheet holder, and some have an attachment that inserts into the film holder slot on the camera back so the photographer can measure light that falls at a specific point on the film plane. The entire film holder/back assembly is often an industry standard Graflex back, removable so accessories like roll-film holders and digital back can be used without altering focus.
Some of these disadvantages can be viewed as advantages. For example, slow setup and composure time allow the photographer to better visualize the image before making an exposure. The shallow depth of field can be used to emphasize certain details and deemphasize others (in bokeh style, for example), especially combined with camera movements. The high cost of film and processing encourages careful planning. Because view cameras are rather difficult to set up and focus, the photographer must seek the best camera position, perspective, etc. before exposing. Beginning 35 mm photographers are even sometimes advised to use a tripod specifically because it slows down the picture-taking process.
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