OK - this will probably astonish many, it is probably known in parts by most, but I haven´t seen this yet put into such a nice, stringent and logical explanation in one run. I am sure this should be posted to all the sections of GetDPI mostly for the smaller sensor cameras, but I post it to Sony now. Maybe the admins put it somewhere to keep as a basic point of start and information.
Watch it ! It is really worth doing. I definitely knew everything in this video, but even I was astonished as of the connection to the advertisements and the actual amount of cheating. I was not "aware" of this......
And finally: of course this works the same the other way upwards to medium format lenses with their bigger lens diameters. The exit pupil´s size defines the brightness of the image. And now you know why we at Hartblei use MF Zeiss glass for 35mm Lenses with very nice results.
Are Sony, Olympus and Panasonic Cheating Their Customers (crop factor with ISO & aperture)? - CanonWatch