I am looking at the Nikkor Telephoto combination 600/800/1200 lens. The one with the interchangeable rear elements. I know the Nikon brochure says the image cir cle is 310mm at infinity focus at f/22, which is just able to cover the 8x10 for mat. Anybody have any real world experience with these lenses to see if they have mor e coverage? I have heard the 1200 will cover 12x20, but per Nikon it won't. I ha ve another Nikkor that give more coverage than the brochure says & wonder if the se big guns do also.