Science Fair Project Encyclopedia
The view camera is a type of camera with a very long history (some modern examples are often mistaken for antiques,) but they are still used today by professional and amateur photographers who want full control of their images. The view camera is basically a light-tight assembly comprised of a flexible mid-section, or bellows, attached to a device that holds the film sheet or plate at one end (the rear standard) and a similar one that holds the lens at the other end (the front standard). The lens and film standards are not fixed relative to each other (unlike most cameras), which allows movements of the lens and film plane in respect to each other.
View camera operation
In operation a view camera has the photographer open the shutter on the lens to compose and focus the image on a ground glass plate on the rear standard. As the ground glass image is sometimes difficult to view in bright light, the photographer may use a "dark cloth" to cover their head and the rear of the camera to assist in composition. A Fresnel lens is also a great help as the lens considerably brightens the ground glass image (albeit with a slight loss of focusing accuracy), or a high quality loupe may be employed for critical focus on the ground glass. The lens may be stopped down to help gauge depth of field effects and vignetting, but is generally opened to its widest setting to aid in focus.
To take the photograph, the ground glass, held within a metal frame, is displaced using springs and a a film holder is inserted. The shutter is then closed and cocked, the shutter speed and apeture set, and the darkslide of the film holder removed, revealing the sheet of film. The shutter is then triggered, the exposure made, and the darkslide replaced into the film holder.
Most sheet film holders are interchangeable between brands and models of view camera, adhering to a single standard. There are special film holders and accessories that fit in place of a standard film holder, such as Grafmatic, which could fit seven sheets of film in the space of an ordinary two-sheet holder, and some light meters have an attachment that inserts into the film holder slot on the camera back that allows the photographer to measure light falling at a specific point on the film plane. The entire film holder/back assembly is often an industry standard Graflex back, removeable so accessories like roll-film holders and digital imagers can be used without altering focus.
Types of view camera
Generally, view cameras are built for standardized large film formats (measurements in inches): 4x5, 5x7, 4x10, 5x12, 8x10, 11x14, 8x20, 12x20, 20x24, and 30x40. In Europe and Asia, the long side is often listed first when discussing sheet film size and the associated view camera equipment, albeit in inches rather than a metric measurement, ie. a 5x4 camera is identical to a 4x5 camera. Sometimes the closest equivalent in centimeters is used as well, ie. 9x12 or 12x9 for 4x5.
Far and away the most popular formats are 4x5 and 8x10, with the majority of cameras and lenses designed for one or the other.
There are several varieties of view camera, engineered for different purposes and allowing different degrees of movement and portability. They include:
- Monorail Camera - This is the most common type of studio view camera, with the front and rear standards being mounted to a single rail that is fixed to a camera support. This design allows the most movement and flexibility, with both front and rear standards able to tilt, shift, rise, fall and swing in similar proportion. These are generally made of metal with leather or synthetic bellows, and are difficult to pack for travel. Sinar and Toyo are popular manufacturers of monorail view camera systems. ARCA-Swiss produces monorail cameras for field use in addition to models for the more conventional studio applications.
- Field Camera - These have the front and rear standard mounted to sliding rails on a flat bed that is fixed to a camera support. These cameras are designed to fold up into a small box for portability, and can be made of wood as well as composites like carbon fiber. The trade off is that the standards are not as mobile or as adjustable as with a monorail design, especially the rear standard, which may even be fixed and offer no movement. Their light weight and ease of packing and set-up are popular with landscape photographers. Extremely large cameras of this type, using 11x14 film and larger, or panoramic film sizes such as 4x10 or 8x20, are sometimes referred to as Banquet Cameras. Such cameras were once used to photograph large, posed groups of people to mark an occasion, such as those attending a banquet. Studio and Salon Cameras are similar in construction, but do not fold up for portability. Wisner and Tachihara are popular examples of modern Field Cameras at either end of the price spectrum.
- Press and Technical Cameras - These are very portable, but often have the least amount of usuable movement of the three main types of view camera. Originally made for news photographers before roll film became popular, they are designed to fold up, with the lensboard in place, in less than a second. Some are equipped with rangefinders and viewfinders for hand-held work, and some antique models have focal plane shutters. These are typically made of machined and stamped metal, designed for daily use by working newsmen, so they are usually very robust, but also very heavy. The Speed Graphic in its many incarnations was the camera of choice for the American photojournalist in the Golden Age of Hollywood and in the Second World War, and used examples are still popular with photography students. Modern examples of Technical and Press View Cameras are still in production by Horseman, Wista and Linhof.
View camera movements
Photographers use view cameras to control convergence of lines and focus. They do this using movements. Movements are the ways the front and rear standards can be positioned to alter perspective and focus. The term can also refer to the mechanisms on the standards that allow the position to be achieved.
- Rise and Fall - Moving the standard up or down in relation to the image plane.
- Shift - Moving the standard left or right in relation the the image plane.
- Tilt - altering the angle of the standard in relation to the image plane by tilting it back and forth.
- Swing - altering the angle of the standard in relation to the image plane by swiveling it from side to side.
Photographers use angular movements (tilt and swing) to change the angle between the lens and the film. 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 lens brings one edge or a corner of the film farther from the lens than the center is; the opposite point of the film is therefore closer to the lens. This can place both near and far objects in focus at the same time. For example, when photographing a field of nearby flowers with mountains in the distance, a photographer can tilt the lens or film, bringing the top (where the flowers are — the image is upside-down on the film) farther away and the bottom (where the mountains are) closer. By doing this, the photographer can have both the nearby flowers and the distant mountains in sharp focus. This is impossible with camera that keep the lens pointing squarely away from the film.
Not all cameras have all movements available to both the front or rear standards, and some cameras have more movements available than others. In addition, some cameras are designed with mechanisms that make intricate movement combinations easier for the photographer to accomplish, such as yaw-free cameras.
View camera lenses
A view camera lens typically consists of:
- A front lens element, sometimes referred to as a cell.
- A shutter, which consists of an electronic or spring-actuated iris and controls both aperture and exposure duration. (On early lenses, air-actuated shutters were sometimes used, and others had no moving shutter at all, a simple lens cap was used instead.)
- A lensboard
- A rear lens element (or cell).
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. A lensboard is simply a flat board, typically square in shape and made of either metal or wood, designed to lock securely into the front standard of a particular view camera, typically engineered for quick removal and replacement for swapping lenses in the field. Not all lensboards work with all models of view camera, though some 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 leaf shutters for view camera lenses. The following is a list of the Copal Number and the corresponding diameter required in the lensboard to mount the shutter:
- Copal #0 - 34.6 mm
- Copal #1 - 41.6 mm
- Copal #3 - 65 mm
- Copal #3s - 64.5 mm
The lens is designed to split into two pieces, the front and rear elements mounting to the shutter and lensboard. This is usually done by a trained technician, but mechanically inclined photographers often do this themselves.
View camera lenses are designed with both focal length and coverage in mind - a 300mm lens may be a normal focal length or a telephoto lens depending on whether it was desiged to cover a 4x5 or 8x10 image area. Most lenses are designed to cover more than just the image area to allow for "movement" - positioning the front or rear standards out of linear alignment for perspective and focus control.
Focusing involves moving the front standard closer to or further away from the rear standard, the lens itself does not have nor need any internal helical focusing device. The lens elements do not need to move in relation to one another.
Very long telephoto lenses or very short wide-angle lenses may require the camera be fitted with special bellows to bring the subject into proper focus, as the regular bellows will be either unable to extand far enough to accomodate long lenses, or collapse tight enough for extremely short ones. "Bag bellows" are common wide-angle photography accesories, replacing the accordion-folded bellows with a simple light-tight leather or synthetic bag. Recessed lensboards are also sometimes used to get the rear element of a wide angle lens close enough to the film plane to achieve focus. Some cameras offer extra-long rails and bellows to mount the standards to for long lens work.
Zoom lenses are unheard of in view camera photography, but there are "convertible" lenses that allow the photographer to add and remove lens elements in the field to alter the optical formula, resulting in a new focal length. These are popular with field photographers who would prefer to save weight by carrying one convertible lens rather than two or three regular lenses. The trade off is a smaller maximum apeture than is usual with regular lenses, and sometimes convertible lenses are not corrected for chromatic abberation, making them useless with color film.
Soft focus lenses introduce spherical abberation deliberately into the optical formula for a pleasing ethereal effect. The amount of soft-focus effect is determined by either apeture size or special disks that fit into the lens to modify the apeture shape. Some antique lenses have a lever which controls the softening effect by altering the optical formula on the fly, similar to modern SLR soft focus lenses.
Current large format lens manufacturers:
- Schneider Kreuznach - Price-no-object high quality lenses.
- Nikon - Noted for its high quality telephoto designs.
- Rodenstock - Extremely high quality, reasonably priced.
- Cooke - Interesting and expensive soft focus and color-corrected convertible lenses.
- Congo - Budget lenses, but offering interesting soft focus and telephoto designs.
- Seagull/Shen-Hao/Sinotar - Budget lenses.
- Sinar - Rebranded Rodenstock lenses.
- Caltar - Rebranded Rodenstock lenses.
- Linhof - Rebranded Rodenstock and Schneider lenses.
View camera advantages
- Large film format allows a very detailed picture and for enlargement with less "grain" or loss of quality. It also allows for contact printing at easily viewable sizes without use of an enlarged negative—the preferred method for alternative process printing.
- The larger film sizes used in view cameras allows photographs made with them to exhibit more discreet steps in the tonal range from black to white allowing for smoother surface tonality on objects represented in finished prints.
- Elimination of converging lines when the camera is angled and looking at parallel lines. As an example, if one were to take a camera sitting on the ground, and point it up at a tall building, the parallel lines of the building would converge at a point. By realigning the front and rear standards of a view camera to be perpendicular to the ground, this phenomenon is elminated. This is useful in architecture photography.
- The ability to place the plane of sharp focus. In a 'normal' camera the lens and film planes are always parallel to one another. By use of the Scheimpflug principle and the Hinge rule , the camera operator is able to place the plane of sharp focus, thus achieving an image with all the chosen elements in focus. Either standard can be manipulated (tilted through the horizontal, or swung through the vertical) to achieve this effect. It must be noted that such movements on the rear standard will also affect the perspective of the image.
- The camera operator is forced to think about the proposed shot. The weight of the camera (and associated equipment such as lenses, tripod, film holders etc) does not lead to simple 'snap' shots. Having said that, many of the famous press images of the 30s and 40s were produced with hand-held 5x4 format cameras.
- Lenses generally have leaf shutters that will synchronize with flash at all speeds.
- Lack of automation: most view cameras are fully manual. Consequently, novice users and even veterans are prone to making numerous mistakes throughout the process. Sinar cameras go some way to making the process less time-consuming, with self-cocking shutters and film-plane metering.
- Size and weight: the old adage "View camera photographers have strong backs and weak minds" may raise a smile from some practitioners.
- Time to set up and compose: not exactly optimal for that image that isn't going to hang around, though Paul Caponigro did get very lucky with his "Running White Deer ".
- Cost: view cameras are often hand-built and made with limited production runs which tends to push up the cost when compared to other, mass-produced, camera types. Sheet film is also quite expensive compared to roll film.
- The long focal length lenses required for view cameras, especially for large format film sizes, are slow and have shallow depth of field compared to smaller format cameras.
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