The sugestion of Camera Settings

[Ratmapper]

Good references!

I think today it is probably wisest to use "full frame" as the norm i.e 135 format film i.e 24x36 mm negative size since all cameras with smaller sensors compare themselves with the "full frame" previously known as "small format".

The number of photographers used to 6x6 cm and larger are getting smaller by the years. When I wrote the original dialogue 6x6 was still used. Now the biggest Hasselblad (medium format) sensor I find is 5.3 x 4.0 cm.

So pretend you have a 24x36 negative, traditional lens set, and crop to the desired aspect ratio.