Folding

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For a list of folding cameras, see Category: Folding.

A folding camera, or folder, is a camera with bellows that can be folded to occupy less space when not in use. Not all bellows cameras can be called folding: a monorail view camera has bellows, but it cannot be folded and instead provides flexibility for "movements" (as well as allowing some compression for relative ease of transportation). The more sophisticated press cameras (like the Busch Pressman) are both in one: bellows camera (for shifts and tilts) and folding camera (for compactness).

A small number of folding cameras designed for shifts and tilts sacrifice portability for flexibility. However, the great majority of folding cameras force the lens board and image plane to be parallel, and the lens and image frame to centre on an axis perpendicular to these two planes. This reduces the function of the bellows to saving of space.

The scope of the term folding camera is unclear. While there is no dispute that the Agfa PB 20 is a folding camera, cameras such as the Plaubel Makina that employ bellows and hinges to collapse when not in use, but for which neither the lens assembly or its cover is hinged in relation to the body, are regarded by some people as strut folding cameras, but are regarded by others as not folding cameras.

Putting aside strut folders (if they are indeed folders), we can divide folders into two. A minority, exemplified by the Voigtländer Vitessa, have "barn doors": a symmetrical pair of doors. The others have a single door. A distinction is sometimes drawn between whether the bed hinges vertically or horizontally, but other than for square format (e.g. 6×6) cameras, normally only held in one way, this distinction too is ambiguous as it is not clear what "vertical" and "horizontal" mean. The great majority of 6×6 folders have the bed for the lensboard below the lens assembly when the camera is held in the normal way; the great majority of 4.5×6 and 6×9 folders have the bed for the lensboard at one side or other of the lens, rather than below it, when the camera is held so that film goes from one side to the other.

The following description is necessarily simplified.

The typical rollfilm folding camera of the 1920s needs to have its lens assembly pulled out when the bed is hinged open. The leaf shutter has a small lever for cocking and another for firing; it also allows a cable release to be screwed in. (The screw dimensions are the same as those used in those of today's cameras.) Film is advanced with a key or knob; one stops winding when the new number appears in a red or orange window on the back. There is no rangefinder, and the only viewfinder is a swivelling brilliant finder attached to the front of the lens. There is no pressure plate to hold the film in the right plane.

Its successor of the 1930s is self-erecting: as one unhinges the bed, the lens pops forward. (It may be necessary to pull it a little further, so that it clicks into position.) The brilliant finder is supplemented by some other viewfinder, also very rudimentary even by the standards of the 1950s. There may be a mask to allow a choice between two formats (e.g. 4.5×6 and 6×9).

By the 1950s, the brilliant finder is gone and a viewfinder, perhaps with integrated rangefinder, is under a rigid housing. The shutter still needs to be cocked, but the shutter release is now on the body. There is certainly a film pressure plate; either this has one or more holes for red windows, or there are no holes and no red windows as film advance is semi-automatic. The lens is focussed in one of three ways:

  • the frontmost element alone is moved ("front-cell focussing"): optically the least satisfactory solution and normal in cheap cameras, but sometimes used for expensive and highly regarded cameras too
  • all the elements of the lens are moved forward and backward together ("unit focussing"): this can be achieved by mounting the lens and shutter assembly on an helical ("helicoid focussing"), or on a strut that moves along a rail or is displaced in some other way
  • the film is moved forward and back while the lens is kept stationary ("film-plane focussing"): the least common of the three systems

There have been folding cameras in all kinds of format, from 18×24 mm to at least 18×24 cm.

common folding cameras special folding cameras
186689148_48cc1cbc5d_t.jpg
a folding bed camera ...
149845564_a2157dad10_t.jpg
a strut folding camera ...
97255477_68678572b7_t.jpg
modern Polaroid,
unfolded
209452190_47950b0e53.jpg

Alike some view cameras the big repro cameras like this Klimsch-Praktika
cannot be called folders despite of the bellows. (camera's total length: 4 meters)

186689140_e93cc17e1b_t.jpg
... unfolded, hinged
lid flapped aside
149850818_d8b45e2048_t.jpg
...unfolded
207294545_fb38bfc6f1_t.jpg
press camera, folded

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