Michael - My enlarger is a 5x7 Omega E6 w/ Omegalite lamphouse, which I've always used for graded Galerie paper; lenses are all Componons (105/135/150/210). Never noticed any corner falloff in the prints, so never checked for lens falloff. Recently did a DIY LED conversion for use with VC papers, so I decided to check the illumination uniformity with each of these lenses when setup for 8x10, 11x14 and 16x20 prints. At each print size I checked at f/5.6, f/16 and f/45. After centering the easel on lens axis, the results with 4x5 neg carrier w/o lens, as well as both 135 and 150, showed very uniform w/o lens but both lenses caused much corner falloff wide open - up to 1/2 stop. Closing down to f/16 reduced falloff to negligible for 150 (possibly f/11 would have done the same) and 1/3 stop for 135. So, yes, there's some slight falloff with 135, but the edges of any print are typically burned slightly anyway, so there should be no issue with falloff.
Larry - I have enough ceiling height to raise my head to the top of the column, but when the power lift failed and could not be repaired I built a gripper (cushioned "pliers") with long handles to reach the manual control knob for fine tuning after the visual focus. Works ok. Would rather have the focus extension device by KHB but it costs more than the enlarger is worth. Some day I may find a way to simulate the KHB gadget with a different mechanical arrangement, but for now I'm functioning.
Last edited by silveror0; 01-16-2014 at 10:14 PM. Click to view previous post history.