Well, I read somewhere (I think here) that the 19" Artar would cover 12x20. I hope it's correct information. I bought the lens on Ebay. It was pretty cheap, so I'm not out much if it doesn't cover.
I'm going to use the camera strictly for straight-on studio still life work, so I won't be trying any extreme movements. That should help.
I just recently had a major surgery but as soon as I'm given the go-ahead to lift more than 15 lbs, I'm going to start heaving the beast around! We'll see how it works....

I may eventually try to put the lens in a shutter. Film is so expensive, I'd like to take out as many guesswork type variables (1 mississippi, 2 mississippi, etc) as possible.

Thanks for all the replies,