I was testing some Kodaline paper the other day, and it had really really long exposures. The included data sheet stated that it was for mainly contact printing or reproduction of halftone images, though the box I had was 11x14. So it really depends on the paper, and as long as the image forms to your liking you are fine. I havent had a chance to try lith printing, but as of what I read their exposures are also very very long.