Haze between elements

I have a 75mm 3.5 TESSAR from a ROLLEIFLEX AUTOMAT with haze between elements. I have read that heating the lens might remove some if not all. Does heating the lens work?

Haze can be caused by a number of factors, so arbitrarily heating the lens can cause permanent damage. Best bet if the haze is caused by oil outgassing or internal moisture is to lightly clean the elements front and rear with a cotton swab lightly moistened with propyl alcohol and dry with another light cotton swab. If the haze is caused by fungus etching the glass, the only cure is to have the lens repolished and recoated $$$, if you can even find anybody today to do it.

Heating a lens mounted on a camera with a leaf shutter would not be advisable, and potentially make things worse, as lubricants could liquefy and get into the shutter. The Tessar is a fairly simple design (4 elements in 3 groups) so it shouldn't be too difficult to clean. A spanner wrench would probably be needed. If you're not comfortable doing the job yourself, then the Rolleiflex may be worth getting professionally serviced.

 

As noted in the previous lens haze thread, if the haze is in the cemented doublet of the Tessar, then it could be cloudiness due to balsam separation. In this case the only option would be to re-cement the elements or use a replacement from another camera.

Edited August 22, 2021 by m42dave

Heating a lens mounted on a camera with a leaf shutter would not be advisable, and potentially make things worse, as lubricants could liquefy and get into the shutter.

 

As noted in the previous lens haze thread, if the haze is in the cemented doublet of the Tessar, then it could be actually cloudiness due to balsam separation. In this case the only option would be to re-cement the elements or use a replacement from another camera.

It is not mounted on the camera, I removed it to clean the elements.

It is not mounted on the camera, I removed it to clean the elements.

 

Then I'm not sure why you would need to consider heating, when it sounds like you already have access to the lens elements for cleaning.

 

I don't know if the lens in this camera is coated or not. If the haze does not clean satisfactorily with lens cleaner, then the coatings or glass may be etched. Again, if it's in the cemented pair then cleaning (or heating) won't help.

Edited August 22, 2021 by m42dave

Then I'm not sure why you would need to consider heating, when it sounds like you already have access to the lens elements for cleaning.

 

I don't know if the lens in this camera is coated or not. If the haze does not clean satisfactorily with lens cleaner, then the coatings or glass may be etched. Again, if it's in the cemented pair then cleaning (or heating) won't help.

It is coated JENA TESSAR T. I have cleaned the elements so that there is no haze on the outer elements. I believe it is between cemented front elements. The rear element has no haze.

I believe it is between cemented front elements. The rear element has no haze.

The cemented pair would be at the rear, actually. If the rear group looks clear then it doesn't sound like balsam separation.

 

It it's between the first two elements then it should clean OK, unless the coating or glass is damaged.

Thank you I had assumed the rear was the cemented piece. There is no damage to either the glass or coating. What method of cleaning would you recommend?

I would first remove any dust. If you use a lens brush, keep in mind that oily haze on the glass can contaminate the brush, so a blower bulb may be better.

 

I usually wrap a piece of lens cleaning paper around the end of a cotton swab, then moisten with a drop of lens cleaning fluid, Windex, or isopropyl alcohol. Camera repairman Thomas Tomosy recommends Windex, and I find it works as well or better than lens cleaner. Clean gently, as internal coatings are sometimes softer.