Hi to all, I am doing 35 mm, 645,4x5 (I have lens 210mm), I want to start 8x10 ,and take picture of faces of people in 1:1 size on the fil m, of course they won't like it , but I like it. And I don't want to have distortion like 210mm on 4x5 ,there is slight one. What lens will you recommend ? I like 100mm lens on 35 mm camera ,So it will be 600mm or 720mm on 8x10 ? Is there big difference on distortion be tween 600mm and 720mm? Please give me any advice Thank you very much.