Today i printed a 6x7 negative and have a few basic printing questions. The exposure was at f11 for 10 seconds and also i had to burn the left side for an additional 10 seconds because the lens was inadequate for a 6x7 negative. At first i thought the negative was popping up or down because of the blurry light on the left hand side but i realized it must be the lens. Im using a 75mm Nikon EL-Nikkor and need to get a 90mm or 100mm to cover a 6x7. Are all Nikon lenses of the same sharpness if its a 75mm, 90mm, or 100mm? Is the contrast to much in this print? I like contrast! The film is Adox developed in Rodinal, printed on Ilford rc paper with no contrast filter used while enlarging.