</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (RAP @ May 17 2003, 08:42 PM)</td></tr><tr><td id='QUOTE'>There is no fall off what so ever and I get sharp prints edge to edge, corner to corner since I am projecting through the best part of the lens.</td></tr></table><span class='postcolor'>
I have often heard that opinion. I agree that this may be a solution to fall-off problems. It may even help getting better sharpness in the corners, if you experience some alignment problems with your enlarger. But it is not generally better and wise to use a longer lens.

First, all decent el-lenses do not fall-off significantly in the corners, if stopped down 2-3 f-stops. Second, if you look at the specs of (el- or LF) lenses, you will find that MTF (and thus resolution and sharpness) decreases as the focal length increases. However, MTF "multiplied with coverage" (i.e. the amount of information projected thru the lens) increases (the reason why LF actually has more resolution and sharpness). But if your lens has more coverage than you actually use, then you will waste some performance. What is left is the lower MTF for the coverage you use.

This usually does not have much impact to LF in practice. Nor does fall-off of a 150mm or 135mm lens have. However, everyone who prints 35mm can easily verify how performance drops with longer focal el-lenses.