DBP said:
Look for a 3a folder with torn bellows. The lens had to cover 6.5" just to cover the postcard format. Be forewarned, though, the lens may be better than you expect.
This is an understatement. I've just completed a little lens torture exercise. On the emulsion I used with the target I chose etc. etc. etc. a CZJ pre-1912 150/6.3 Tessar produced images that can't be separated from ones made at the same apertures with two 150/9 Apo Ronars and a 150/9 G-Claron. Makes me wonder why I bother acquiring relatively modern lenses.
I couldn't mount up my ex-3a B&L Zeiss 5 3/8"/6.3, but I included a ~ 7"/6.3 B&L. Same story with it, but images taken with it stood out a little because of the slightly higher magnification.
Sam, if you want a crappy old lens that will take crappy pictures, look for a no-name Goerz Doppel Anastigmat. NOT a Series III, those are Dagors. The no-names are cheap dialytes and the 130/6.8 I have is flary, unsharp, basically not fit for use even though the original purchaser probably loved it.