Leica LTM Summaron 3.5 self destructive glass

Leica M39 screw mount bodies/lenses

Quasind

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I bought my first Leica (IIIc) in 1971. I asked for the 35mm Summaron f3.5 lens, it is still mint -. Recently I noticed that the internal elements were evenly covered with a fine fog, similar to spray paint overspray. I contacted Don G for a CLA and received this reply:
"The Summaron lens usually is difficult to improve when it has a million super small dot-like white spots inside the inner lens elements from gases of the metals inside the glass spewing out & depositing on the glass surfaces. At best I may be able to clean it 10-15% & at times cleaning will make it worse. The worst part is that I wouldn't know if cleaning will make it worse until I actually try cleaning it so it's taking a chance, "

I imagine other Summaron lovers have faced a similar dilemma, has anyone found another solution? Anyone have good results with the CLA or had regrets about doing the CLA?
 
My LTM Summaron 35 is in the same condition. Plenty of small, mistlike droplets of the lens surfaces on either side of the diaphragm. Its been said that the glass/coatings used on these lenses in their day were very soft- any attempt to clean them would make their surfaces worse. These were so soft that moderate cleaning is enough to blemish them even more.

I've never been able to open my LTM Summaron 35, since getting in it seems to be 1000X harder than correctly placing the squares in a Rubik cube in their proper sides. However, I've been able to work on an M-version of the Summaron. It seemed to be far easier to take apart. This lens (not mine) had already been scarred by fungal growth and it too had a cloudy deposit within when its owner sent it to me.

I got the lens stripped down to its aperture blades. Dismantling the aperture was a very very very bad idea- the blades fell out when I inadvertently took off the wrong screw. Getting them back is a real nightmare :D. Going back to the misty deposit on the lens, the fogging was removed with a simple wipe with Windex. In as far as I can tell, the cleaning procedure did not add new blemishes.

In the end, the lens still remained blemished since the scars left by ancient fungal attacks had already been etched into the glass. The lens looked much cleaner than it was prior to cleaning. It could shoot 'clearly' with satisfactory results, as long as it is not pointed against bright light, or used for shooting contre-jour, or it there are no very bright highlights in the objects in the picture. Resolution-wise (I've been able to shoot it only on digital) though, this Summaron still did good.

Jay
 
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