Fungus and reconditioned lenses

[nickthetasmaniac]

Hi all,

I've been looking for a short tele for my newly acquired M2 and have found a very nice looking 'fat' 90/f2.8 Tele-Elmarit. The seller has receipts for a recent $400 refurb from a well respected service centre, but the documentation mentions that the lens was cleaned of fungus.

It looks mint, so I'm just wondering if people have had issues with older lenses and fungus after being refurbed?

Cheers, Nick

(Appologies if this should be in the 'Optics Theory' area or somewhere else... I'm new to the forums)

 

[peterm1]

I would just query the seller to find out if the service centre indicated that the removal of fungus was not accompanied by any damage to the internal elements' coating. I suspect that any version of a tele elmarit including the fat verison would have sufficiently hard coatings that it would be unlikely to be an issue - earlier lenses often had coatings that tended to be much softer, but coating technology began to improve greatly by the mid / late 1950s. Prima facie, if the receipt does not indicate that there was residual damage then it suggests to me that (a) the cleaning successfully got rid of any fungus that was present (something that is not always possible) and (b) there was unlikely to be damage to the coating from the cleaning process. Speaking personally I have never had problems caused by cleaning the internal elements of a lens but sometimes it has not been possible to get the glass completely clean without risking damage to the element coating so a trade off has to be made. A small amount of residual fungus will almost certainly not affect images - residual fog is a worse problem.