This is a wood camera I made using an old Polaroid 110A Pathfinder lens (Rodenstock). It is a coated lens which is very sharp, 127mm. My friend uses one on a 5X7 she has and it covers pretty well, except for a tiny bit of the corners.
I've cheated, because mine has a focusing capability. Borrowed the view finder components and focusing scale so I can guess at distences. It works very well, basically a step up from the pinhole concept, but cheap and with a shutter.
There are plenty of lenses which cover different formats, find one which works and build a box to accept a film holder, then you're ready to go. An 11X14 box camera would be interesting, but a bit bulky to carry around and work with. tim