I just tried doing a 6x7 from my new-to-me Mamiya and for the life of me I could not get good light coverage of the entire frame, especially on the long ends. I did remove the 35mm condensor (bottom) but checking the easel with no negative clearly shows a very vignetted light. I left in the top condensor and in fact tried every variable of condensor (35mm only, 120 only, both, none...) and nothing worked. I believe the top condensor was labled 6x6 but I honestly didn't even see it covering that much evenly. I tried two different 105mm lenses from between f/5.6 up to f/16 and saw no siginificant difference in the vignette; it's clearly the light source. The same lens works fine on my DII with a cold head. Any suggestions? I would much rather use this enlarger, even for B&W over my DII. With the 150 control it makes contrast adjustments a snap!