Wikia

Twin Lens â€” The camera uses two equal lenses, one for viewing and for taking. Reflex â€” Refers to the mirror used behind the viewing lens to make focusing possible.

the typical TLR: for 6×6cm frame size, image by Elmo Alves (Image rights)

6×6cm TLRs, image by wedste (Image rights)

Twin Lens Reflex (TLR) cameras are "two-eyed" cameras such as the classic Rolleiflex. They normally consist of two equally constructed lenses with equal focal length and equal "speed". They are mounted in the front of the case, and their focusing is synchronized so that they are always focused on the same distance. The difference is that the one lens projects the incoming image via mirror up to the reflex finder's ground glass whilst the other lens projects the image into the camera's dark chamber onto the film plane. The camera lens can be stopped down whilst the finder lens is always at maximum aperture.

The scene viewed by the top lens (the viewing lens) is reflected by a mirror onto the ground glass screen so that the image seen on the ground glass is back to front (left is right, right is left) which can take some time for getting used to.

The bottom lens (the taking lens) exposes the film. This means that, unlike SLR cameras, the viewed image is not exactly the same as the image recorded on the film â€” the difference being the distance between the centre of the viewing lens and the centre of the taking lens. This discrepancy is known as parallax error, which can be corrected by lifting the camera until the taking lens is as high as the viewing lens was when the image was composed.

Well-known TLR manufacturers are the German Rollei, the Japanese Yashica, and the Chinese Seagull. Popular and beautiful TLRs were also made by Japanese companies such as Mamiya prior to the 1970s, lomagraphists prefer the old Soviet LOMO TLRs.

The vast majority of TLRs take 120 film and expose 12 pictures in 6Ã—6cm format. Some models did take 127 film and expose 12 pictures in 4Ã—4 format, and there are a few models using other formats (e.g. the Superfekta and Ontoflex took 6x9cm images; the Agfa Flexilette and Contaflex TLR used 35mm film). Recently, several "toy camera" class 35mm TLRs have been introduced (Blackbird, fly, Gakkenflex).

ProsEdit

TLRs are typically very quiet. Viewfinder image matches image size on film. No viewfinder blackout during exposure. TLRs use leaf shutters, which can sync with a flash at any speed. TLRs are waist-level cameras. Subjects are usually more relaxed and less likely to pose for photographers using waist-level cameras.

ConsEdit

Parallax is a problem at close distances. Reversed image (image is upright but reversed left to right). Unlike an SLR, no impression of depth-of-field can be given in the viewfinder, as the viewing lens has no diaphragm. Most don't have interchangeable lenses (exceptions: Mamiya C series and Koni-Omegaflex). Can be relatively large and heavy (depending on brand and model).

Pseudo TLRs are simpler versions of a "full" TLR, but without the focusing features.