I have a 35 Summicron M that I got used and when shining a flashlight through it from the front, I notice tiny spots on the inside of the rear surface. They look almost like oil from the blades might have evaporated onto the lens surface, as they seem evenly distributed over the entire surface. When shining the light through from the rear of the lens, all looks clear. All also looks clear when examining the lens by eye without at flashlight and just looking through it, etc.

Is this anything to worry about in terms of affecting image quality? Or, am I being too uptight?

-- Tim (emulsion71@hotmail.com), March 07, 2002

Answers

Tim: It sounds like the standard Leica fungus. It tends to soften the image as well as reduce contrast. What is the serial number of your lens? Several of my older lenses have this, and I have had two of them cleaned. Looking at slides as a comparison, I have not noticed a big difference in the ones with the fungus, but it does show up on the B&W. I am not as critical as others on this forum, but I do enjoy a GOOD photograph.

Enjoy your lens, and if the pictures are not good enough, then see about getting it cleaned.

-- Mark A. Johnson (logical1@catholic.org), March 07, 2002.

It's a 90's (from what I understand) Summicron 35 with serial number 3681575. Given my description above, does it sound like something I should worry about?

Also, how would it affect black and white differently than color?

-- Tim (emulsion71@hotmail.com), March 08, 2002.

Tim,

I don't believe that your problem is fungus. Fungus never looks clear. It sounds more like oil, as you suggest. I have an Olympus Zuiko 50mm/3.5 macro lens (bought used) that has the same problem you describe. The pictures I get from it seem not to be affected, however. I suspect it was caused by the lens getting excessively hot (maybe left in a car in the sun?), causing the evaporation of oil that subsequently condensed when the lens cooled.

-- Ray Moth (ray_moth@yahoo.com), March 10, 2002.

Tim. The SN 368XXXX indicates a very recent lens. Therefore, I would consider a problem that originated at the factory. Seems a little too short a period of time for fungus or leakage of oil, both of which tend to occur over many years. But separation of the lens elements is a not uncommon problem in relatively new Leica lenses. (I have returned one under warrantly for this problem). I would send it to an expert repair person such as DAG or Leica USA for an opinion, quote, and service, if required.

-- Eliot (erosen@lij.edu), March 11, 2002.