I've heard so many contradictory things about the crop factor of a 645D to FF or APS-C camera.
On THIS very forum, when the 90mm f2.8 was announced, the official post said it was equivalent to a 60mm on APS-C... Um, what? How can that be right. 90mm on 36x24mm is equiv. to a 60mm on a 1.5x crop... so unless the 645D has a full frame sensor... which it doesn't... that's wrong.
Now I realise it's not 'simple' because the 645D is 4:3 not 3:2 but by my maths - I get that a 645D lens, you should halve it, then add a bit, to get an equivalent length on APS-C - that is, the 90mm on 645D would be about 47-48mm for us APS-Cers...
Am I wrong?
Last edited by Tom S.; 03-09-2013 at 05:49 PM.