Hazy collapsible Sonnar

[Philip Whiteman]

I suspect that the latest collapsible uncoated Sonnar I have obtained is not going to be nearly as good as the nice clear one that came with my original bargain-basement Contax II. Has anyone out there taken one of these lenses apart? Can they be cleaned - and if so, does getting rid of haze on the internal surfaces give a worthwhile improvement?

 

[mcfingon]

Not in my experience Philip. I have a hazy 1937 Sonnar 50/2 which I have cleaned. It remains hazy. You may be lucky if it's just a bit of beginning fungus which can be wiped off, but etched-in fungus won't budge and some dispersed lubricants also seem to etch or adhere to glass. The coatings are coming off my particular lens and leaving a rough surface on the glass.

 

[charjohncarter]

I have a 35mm Serenar f3.5 (Canon) that hazes over and over again. It is very easy to take apart and clean so I do that when ever I use it. Someone on this forum said that the glass they used hazed, and in my experience they are right. But there is a definite improvement in performance. It is still low contrast but the halo is gone.

Before cleaning:

Puerto Vallarta 2010 by John Carter, on Flickr

After cleaning:

Tmax400 HC-110h by John Carter, on Flickr

But this is not a Sonnar so if as above says and the glass is etched you may be out of luck.

 

[Grytpype]

It is an exceedingly easy lens to take apart, Philip. Brian Sweeney did a write-up on this forum several years back, but I don't think he is active here anymore and the pictures are missing.

If it would be helpful to have the pictures drop me a PM with your email address and I will send the page as a ZIP file on Monday. I have it archived, like everything else useful I find online!

Steve.

 

[Philip Whiteman]

Thanks all - I will have a go at stripping the thing down and report if there's any improvement or the haze simply comes back!

 

[Philip Whiteman]

Hmm; fell at the first hurdle. My Sonnar did not want to come apart, even following Brian Sweeney's excellent step-by-step guide kindly emailed by Steve. Perhaps it helps if you've done one before, but the degree of force I was putting on the poor old thing to no avail had me worried I was going to break something.

For the time being I shall stick to Plan B: using an absolutely mint 1959 Jupiter 8 found on eBay for picture taking and saving the Sonnar for display.

Sneaky thought: do Jupiter lens elements fit the Sonnar body? I have read that the J8 was recomputed to suit Russian glass, which suggests they'd need setting up, but it's a wicked thought...

 

[charjohncarter]

If you ever get the Sonnar apart, just snug the rings back it place. I have them on my Serenar so I use a toothpick to disassemble.