I'm interested in buying an old lens to cover 4x5. A lens that will vignette and lose sharpness to the edges. I have no idea what I'm looking for on ebay. Does anyone know of a certain manufacturer or time period I should be looking for? Also, I'm looking for something in the 120mm-150mm range (in 4x5). From what I've researched, that's around a 5" or 6" lens? Is this correct? Thanks for all help!