The principle of a single-lens reflex camera, of course, does not at all depend on the size of film it uses; after all, earlier in these pages, we saw how the first single-lens reflex cameras used larger formats of film before the Kine Exakta came along.
The Agiflex dates from 1946; the company that made it had been making basically the same camera during World War II for the use of the British armed forces. It was said to strongly resemble the Reflex Korelle from Germany, but it did not attempt to be an exact copy; I managed to find an image of that camera, which is shown at right, from a British photography magazine from 1936. It took square photographs in the 6x6 format.
Shown at left is the Pentax 6x7, which dates from 1969. It uses 120 roll film, but in design it strongly resembles a typical 35mm SLR, including the pentaprism.
At left here is the Hasselblad 1000F, a large format camera which is greatly renowned. It was introduced in 1957. Later models, with different numerical designations, such as the 500C and the 500C/M, were very similar in appearance.
This camera used leaf shutters in its lenses. (And so, at this point, one almost hears the voice of Kodak, proclaiming that its choice of using such a shutter in the Retina Reflex is vindicated.) As is obvious from the photo at left, it eschews a pentaprism, just having a waist-level finder. However, if you really want to take photographs while looking forwards, the PM-90 and PME-90 (the latter including exposure metering) are available as accessories for the Hasselblad 500C to add a pentaprism. There are also accessory 45 degree finders to allow a viewing angle intermediate between that of looking down or looking forwards.
The standard back for the camera carries 120 roll film, but backs which use other types of film are also available for the Hasselblad; it can be made to use Polaroid film, and later in its life a digital back was introduced.
The Hasselblad was used by astronauts on the Apollo moon missions, and other early NASA space missions. It is perhaps best known, however, as the preferred choice for fashion photography, and studio photography in general.