Quote Originally Posted by Ian C View Post
The Omega D5/D6 has long tapered bellows to accommodate 150mm lenses. That coupled with the small receiver for the slide-in lens plates makes it impossible to bring a 50mm lens close enough to focus an image large enough to make a borderless print larger than about 8” x 10” (some lenses can just barley make 11” x 14” due to a slightly longer flange-to-film distance ). Because the bellows are fully compressed the lens is simply too far from the negative.
Sorry Ian, but this is wrong.

I have no trouble doing 16x20 prints from 35mm negative with my D6 and either my older 50mm f/5.6 Rodagon lens or my newer 50mm f/2.8 Nikon lens - provided I have the correct lens mount and correct lens plate for the lens, and I remove the masking accessory.

Please note that there are some 50mm lenses that don't work with the D6, but as I understand it, that is due to the configuration of the back of the lens (it interferes with the mount).