Archived posting to the Leica Users Group, 2000/07/13
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Robert >>Or even a $450 Cosina 15mm Super Wide Heliar, which has no filter thread << Somewhat related to the topic of filters (UV and otherwise) and the 15mm Heliar, yesterday evening I noticed some really strange illumination issues in some negatives I just developed. I scanned about 8 rolls of film and the issue existed in a couple of dozen images. At first I thought I'd taken the faulty shots with my 28/2.8 Elmarit R and a filter caused vignetting. I use a 55mm B+W polorizer with step up ring. I've never had problems with that in the past. After closer examination I realized the lens used was a Heliar and the camera was my M6. It sort of looked like shutter bounce, but I ruled that out. The issue/problem is a very noticable darkening on the right and left borders of the frame. It only occurred in photographs taken in bright sunlight. Nearly identical photographs taken the day before under overcast skies didn't show the problem. Perhaps it had to do with the aperture used. I'm at a loss to understand the problem, but and I plan to get to the bottom of the problem. Anyone else out there experience unusual light fall-off with the 15mm Heliar? Dave PS I'm not ready to blame the Heliar, yet. I've used it a great deal and I've never had problems before. I still need to do some research.