Bellows

folded bellows of a folding camera seen from film chamber

A bellows can be integral or optional part of a photographic camera and serves as alternate lens tube or lens tube extension. For photographing a bellows has to be expanded to its working length. Most bellows cameras have a front door upon which the bellows unfolds when the door's opened for camera usage. More sophisticated bellows cameras allow to fix the bellows in various positions to optimize the image plane for special applications like architecture photography.

As optional part of a camera for exchangeable lenses a bellows extends the lenses' capablities to make images of small objects in small distance by extending the lens tube's length. Therefore such a bellows can be fixed in as many lengthes as the maximal length of its guide rails allow.