Cloudy individual lens in Mamiya Sekor Z 100mm

[Steve Gardner]

Hi All,

Ive been a lurker on this forum for a while now particularly regarding the issue I faced with a Mamiya RZ 110mm lens. The story so far.......

I hadn't used the lens in quite a while but when cleaning all my kit, I held the lens up to the light and I saw this.....

This looked like balsam separation to me,so I removed the elements from the rear group and found that the issue was between the doublet lens pair. I figured that I had nothing to lose so I read some posts on this forum with a view to repairing the lens

I managed to separate the doublet and after cleaning off the old balsam the larger part of the doublet cleaned up perfectly with no blemishes at all. However the thinner lens has got a lot of cloudiness and nothing I have done so far has been able to clear it off (See the following jpegs)

So I'm wondering what this cloudiness is and if there is a way to remove it. Using acetone, alcohol or lens cleaner doesn't touch it.

Seems a shame to give up on this when the other two lenses in this group are now perfect so if anyone has any ideas I would be grateful.

Kind regards

Steve

 

[Nodda Duma]

Have you tried warm water and soap?

 

[Steve Gardner]

Have you tried warm water and soap?

Hi,

Many thanks for the reply, I hadn’t so I just tried it but unfortunately it’s no better. It’s almost like it’s within the glass rather than on the surface but I don’t know if that’s possible or not However despite saying that, It does seem like it’s on the surface of the lens that had the balsam on it.

Thanks again

Steve

 

[Nodda Duma]

If water didn’t work, and the variety of solvents didn’t work, then this might be a glasstype with low stain resistance that absorbed something either during manufacture or from contaminants in the balsam. If you look through it (not shining a light at glancing incidence) is it apparent? If not it won’t really affect the imagery. If so, then it could be pitch polished away.

 

[Steve Gardner]

Hi,

When the lens is reassembled then you can just about see the haziness even without shining a light through it although it is faint.

Pardon my ignorance but what is pitch polishing?

Thanks and regards

Steve

 

[Nodda Duma]

Pitch polish = how lenses are polished.