Originally posted by narual Why would the image be tossed? Because square paper isn't the most common? You lose a chunk of the image any time you print on 'standard' paper sizes larger than 4x6 anyway. By that rationale, camera sensors should be 4:5 instead of 2:3, since that is would cause the least cropping among common paper sizes. And there are plenty of other places besides instagram to display photos electronically, square or otherwise. Here, for example.
Of course. That is why the actual real "commercial" formats were 4x5 inches, then 5x7, 8x10 (view cameras). In medium format, the ideal was 645 which gave the "less" cropping or "biggest usable image" for commercial purposes.
The 24 x 36 mm frame we got by accident, from "adapting" 35 mm MOVIE film to a "double frame horizontal" format for still pictures. Remember the so called "half frame" format from Olympus Pen cameras.
It was all about sucking every drop of juice from the available media (film - negative size - frames per roll) and about image quality for commercial or home printing.
With digital, we may have a bit of everything from the past, but not as limited. Frames per roll now translate to frames per memory card, then on frames per storage media (cloud, hd, blu-ray, dvd, cd, etc...) Of course, image quality plays a big roll here, but the limitation comes from the image sensor size. That is where the big cost happens. If it was only a matter of using a larger sensor (to match film frame) on older gear, how come this becomes a big issue and took Pentax 15 years to develop (at a reasonable cost). Canikons have it from 7-8 yrs ago, but they have the name and the customer loyalty (and market share) that allows them to gamble with those products.
If sensor size is not the big limitation, then why even Hasselblad or Mamiya has not produced a full size 6x6 (cms) sensor? Or even a square one, any size?. Short answer: COST!