Those of us brought up with the square format of 6 x 6 or 4 x 4 cm film can remember the delight of not having to move the camera. Printing to any size of paper (either landscape or portrait) was routine should the composition, or customer, demand it.
With modern sensors, the same number of pixels could be arranged as a square rather than as a 1.5:1 rectangle. The area of coverage on the film plane would be the same so there would be no question of having to have a difference in lens mount or focal length. The result would be as shown in the following diagram: a 29.4 x 29.4 mm sensor rather than a 36 x 24:
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| A Square vs a conventional Rectangular Frame Size The red and blue frames have identical areas and therefore the same number of pizels |
Shock, horror may be your response—we would lose pixels along the horizontal. Yes, you would but not that many. My D810 would have 6011 x 6011 instead of 7360 x 4912, for example. But—shock horror—the camera would be bigger. Yes, it may have be be taller by 5.4 mm but it could be shorter horizontally by the same amount—and think of the ergonomic advantages whether hand held or mounted on a mono- or tripod.
The Micro Four-Thirds sensor goes some way towards a square format (1.3:1) but the manufacturers did not go the whole way.
Would I buy a ‘full-frame’ camera with a square sensor, smaller horizontally but larger vertically? Yes. Will one ever be manufactured? No chance. As I said, I never cease to be amazed by the ways of photographers still alive and well with the technological legacies of the 1950s.
