Fungus & mold - opinions sought.

[Kintokoba]

Hello all,

I have been offered a kit that if in perfect condition would be a dream come true for me. Sadly there are blooms of fungus on all of the 3 lenses.
I dont know if the fungus is the variety that can eat into the lens coating - lets assume it is- what is the effect on a final print? The damage is primarily around the edges.
I would normally not go anywhere near mouldy optics but this possible bargain box of Zeiss Distagon's has brought me to type this enquiry

Many thanks.

[Matt_Bigwood]

I'm by no means an optical expert, but I gather that mould can eat into the glass, and I'd guess that the contrast of the lenses would be much reduced by the mould, and would particularly suffer if you used it to take a picture with the camera pointing towards a light source, but I'm sure others on this forum will voice their more informed opinions!

[Kintokoba]

Good point Matt. It's hard (for me anyway) to imagine mould being toxic enough to eat into lens coating. Apparently the corrosive variety of fungus is quite rare. http://www.mypentax.com/Fungus.html
I wonder if a lens clean would fall into the same price category as a CLA, i.e. around £60?

[George Hart]

May I suggest that you contact http://www.newtonellis.co.uk/ and ask their advice. I have no connection with this company other than as a satisfied customer!

[Trail Images]

I bought a used lens years ago from a well known used camera vendor. I did not see anything at all wrong with the lens at first, but after using it and having film returned I noticed slight irregularities on the light table with the processed images. As a result I took a magnifying glass and really checked the lens out closely and saw the issues. I had never seen this before in any lens I've owned and sent it back to the vendor. They very quickly recognized it as a fungus taking over and immediately replaced the lens with a like unit. To be honest I'm not sure there is any repair for such a thing, but would be interested as to what you find out overall. Good luck with the research and hopefully there is away to salvage those fine lenses.

[patawauke]

Where are the 'fungus blooms' exactly, and what do they look like? Does it consist of spreading spores on the front or inner lens surfaces, or within the elements? Or single white dots? Usually it is fungus attacking the glass, but I believe some types are said to feed off older between-lens cement. As the poster said, there are many different types. But some really do etch out glass if they take a real hold.

If you want to keep the lenses, I'd suggest you first place the lenses in strong sunlight with diaphgram wide open for a few days (OK, I know it's hard to find that in Britain at the moment) or some recommend UV lamp treatment, to try to arrest the spread and possibly kill the live spores.

Where you can reach the fungus, daub briefly with any of: lens cleaning liquid, slightly dilute vinegar or ammonia, denatured alcohol etc. Sharp edged or pointed tools are not a good idea for obvious reasons, however one website suggested the rounded end of a wooden chopstick for nudging any stubborn spots. Discard any brushes/wipes (or chopsticks!) immediately after use. Do all this somewhere away from any other camera gear to avoid cross-contamination. Repeat the treatment if needed. This should help remove all except the most resistant types of fungus. If the latter persist, you're in trouble, as probably the glass surfaces will be permanently scarred, even a little. Only very expensive lenses warrant a regrind by a specialist, and even that can change the lens characteristic.

There's lots of good information on this subject on the forums and general web pages, so do some homework and keep google-searching.

[Kintokoba]

Thank you very much for your helpful replies!

The 3 lenses, a 50mm, an 80mm and a 150mm all have issues.

The 150 is by far the worst as it has the 'cloudy fog' type mould and the 'spreading spidery virus' type we see after a holiday in the tropics (if that makes sense.. )
It seems to be on the inner rear mainly although on one lens it is right at the front inner around the edges.
The 50mm has what looks like frost on an inside window in winter around the edges, I'd imagine that it would be ok at this stage and probably respond to UV.

I'm going to see if I can put a roll of film through and I'll call the number George has suggested and see what they have to say.

Many thanks indeed!