Stain under front element. Helios 44

[robertofollia]

Dear all,
maybe this should be in SLR, as the lesn is from a SLR, but the provenance -imho- makes it more suitalbe as there are more experts in this subforum. Feel free to move it somewhere else if you consider it approppiate.

After 3 years of continuous use -or abuse- my trusty Helios-44 has developed this -don't know how to call it- stain under front element
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Does not affect quality of image but.. I'd like to get rid of it
I would say it's not fungus, but I've got the doubt about delamination or, simply, oil separating from grease that found its way where it should not be.
So there goes my question
If it's oil it should be cleaned. But can it be cleaned?
I mean, it's just a matter of taking out front element.? ( I mean I hope and guess won't have to separate any glued or cemented elemen ts, in that case it would be a definite no-no)


I would be very grateful if somebody could enlightnen me about that stain and how to get rid of it
Best regards
Robert

 

[Barry Kirsten]

Hello Roberto, It's a bit difficult to be certain from the photos but I'm inclined to think that it is fungus. There aren't the characteristic threads usual in fungal infestations, but separation is quite different and doesn't have the appearance the inner patch has. Whatever it is, if you want to get rid of it the only way is to separate the elements, clean and re-cement them.

 

[Brambling]

this is hardly a gluing.

 

[Ricoh]

Aren't the lenses so cheap and readily available to make junking and replacing a sensible option.

 

[Barry Kirsten]

this is hardly a gluing.

True! I should have remembered as I've had mine apart. I'd say it's fungus then. Sure these are cheap but if it is fungus it could be removed at little or no cost. Be careful of the coatings though.

 

[robertofollia]

Thank you so much for your valuable replies, especially for the cross-section.
Being front element alone it will be a matterof unscrewing name plate and after unscrewing retainer.
I will use D. Leitz's formula (WW 1 time) receipt, that is ammonia+hydrogen peroxide (I badly worte demineralised water), at 50%. This gave me excellent results with lenses really contaminated with fungus .
Wil come back with the results
Best regards and thank you

 

[Barry Kirsten]

Roberto, it's not difficult to get the lens apart. But the front nameplate doesn't unscrew. In my 44M-7 it is made of plastic and clips in with several 'prongs' which will probably break off when you try to remove it. When re-assembling the lens I had to use Blue-tack to secure the plate. It works and nobody would know the difference. This is just one example of the mechanical crappiness of these lenses. Mine had a sticky iris when I bought it and after many hours trying to make the aperture work freely I had to give up and set it as a fixed f/4 lens. But it's optically beautiful and produces lovely out of focus backgrounds. The ammonia formula seems right to me and can't do any harm. Good luck with the cleaning.

 

[robertofollia]

Dear Mr Kirsten
Yes, my 44M-6 is like yours, what intrigues me. Nearly all 44ms I have seen had he screwed nameplate made of alloy, but yours and mine have the plastic 3-prong type, clipped (yes, mine broke one prong, too). That make sme think... is it a 44m-4 and during these "hard times" (after the USRR collapse) did somebody change the name plate for the 44m-6 just to make them look more valuable?
We will never know.
Tomorrow I'll try to take apart front element and come back with the results
Best regards

 

[robertofollia]

Update from today. front element looking pristine. At the first contact with ammonia, just before Imixed it with Hydrogen peroxide, the fungus or whatever it was, vanished. I used a demak'up pad very gently. After that rinsed it with water, let it dry and cleaned with a microfiber optical cloth. So lens looking pristine again.
Thank you all for your advice.
Best regards

 

[Barry Kirsten]

Well done Roberto. I'm glad it worked out for you. Optically these are beautiful lenses.