Cleaning lenses internally (fungus)

[onomatopoeia]

Anyone know anything about this or a place that can do it if it is possible to do at all? My Minolta 70-210 f4 (about 20 years old but bought a couple of months ago) has patches of fungus on the inside of the front and rear elements - my fault for not checking it closely enough before leaving feedback on ebay unfortunately.

I'm wondering if it's worth taking it apart and trying to do it myself, in near mint condition the lens would only be worth about £150 on a good day (it owes me about £80). So the choice is between try to do it myself and maybe break it, pay someone else (who? how much?) or just accept that it's an expensive paperweight and buy the new Sony 70-200 f2.8 G that I really wanted in the first place .

[Steve Evil]

I'd have a go at doing it yourself, you may succeed and will be pleased with your skinflint logic, or you may fail and console yourself with a new lens, whilst justifying the purchase by saying that the old one is in bits and you have forgotten how to piece it all together again.

[Simpo Two]

Firstly, do the patches affect the image?

[malc350]

I think you'll find it's "paperweight-time" I'm afraid as fungus etches into the glass. It can be cleaned off but will leave marks.

Dust, oil on the aperture blades and sometimes coating marks can be removed and often even scratches on the front or rear elements may have little or no effect on image quality but fungus is the one thing that permanently damages the glass and turns it into junk.

Sometimes I'm into the old Olympus OM gear for old time's sake but some of the stuff I've bought on Ebay (thankfully for very little money) has had fungus and I've just binned it.