Tag: camera bellows

Wikipedia says: In photography, a bellows is the accordion-like, pleated expandable part of a camera, usually a large or medium format camera, to allow the lens to be moved with respect to the focal plane for focusing. The bellows provides a flexible, dark extension between the film plane and the lens.

Two kinds of bellows are commonly used on cameras; bag bellows are normally used with a lens of short focal length, and accordion bellows with a much longer range of extension. For large format cameras, “double extension” refers to bellows that extend to a length equal to about twice the focal length of a standard lens, e.g. 300 mm for the 4×5 inch format. “Triple extension” for the same format indicates bellows extension of 450 to 500 mm.

Bellows allow movements that can be used to correct distortion in a photograph and to avoid converging or diverging verticals. Use of a bellows-based camera can ensure that parallel elements in a scene remain parallel in the final photograph.