Archived posting to the Leica Users Group, 2000/02/10
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 09:20 AM 2/10/00 +0100, a couple of folks wrote: > > I'm well aware of the debate on UVA filters re: Protection vs Image > degradation, but > > I've noticed that the UVA filters on my 35mm and 90mm Summicrons are giving > unwanted reflections as night. > > I've shot some night scenes of Sydney Australia and I can read the neon > naming signage duplicated up in the Sky (reversed). > > The same shots without the UVA filters are OK. *** Duh! *** > >Peter, I don't have an idea but I can tell you that a filter on a Nikkor >85mm/f2 gave me exactly the reflections you describe so the >problem is not limited to Leica glass. > *** Duh again! *** I am still amazed that people think that there are no problems associated with using a useless filter on the front of their lenses. Leica lenses WERE NOT designed with a filter in the calculation. So what the hell do you expect. Do you expect to stick two more air-glass surfaces in front of your lens and have the whole system work as if it weren't there??? Give me a break. The Leica web site says: "UVa-filters. In certain back-light situations and in case of great contrasts however, they might also cause unwanted reflections" "typical for any filter." Does this have anything to do with what you are seeing? Could Leica possibly be correct? Could the Leitz optical engineer who said "If we had wanted a flat piece of glass on the front of our lenses, we would have designed it there. But we didn't." know anything about what he is talking about? I guess not. On the engineering and manufacturing side we have "Filters can and will cause problems. Use them with caution" and on the other side we have "Leica engineering has no clue. They don't know what they are talking about. But what are these unwanted reflections I'm getting in my pictures?" This is not rocket science folks. You can believe what you want. Weld those filters on those lenses. I could care less. It's your pictures. Flame me all you want. It is simply not going to change the science of optics. My delete key gets lots of use. But listening to those of you who continue to say (in a squeaky voice) "leaving a UV filter on my lens all of the time cannot degrade my images" really defys logic. It is absolutely wrong. It has been proven to be wrong. It defys optical science. Either wake up or don't complain about crappy pictures. Jim