I've been using this lens for about a year now on a 4x5. Coverage is WAY more than adequate for 4x5. Sharpness and contrast are excellent. I've used it from magnifications from 1:1 through infinity with equal success. It's a great lens if you don't mind F9 which makes focusing more difficult. I've also used the G-Clarons is assorted focal lengths so I was use to that.