Nice Side by Side: Fuji GFX and the Pentax 645Z - mirrorlessrumors It should be pointed out though: - Fuji GFX is a TRUE 44x33mm system. Its not a crop. The mount and the lenses are designed for 44x33mm. - Pentax 645 is a 645 aka 56x42mm system. Thus the 44x33mm sensor is now a crop. Thus the lenses are larger than they need to be, the mount is larger than it needs to be, and the mirror box is larger than it needs to be. There is no 44x33mm DSLR out there ... the closest would be the Leica S system with a 45x30mm sensor. Thus thats the comparison they should have done.