Question about separation

[dogberryjr]

The good news: I finally found a reasonably priced Summar!
More good news: The glass is fairly clean.
The not-so good news: There is what I believe to be separation towards the front element. It goes all the way around the glass to a width of about a quarter inch. I took some test shots with it, and I can live with the resulting image characteristics (photos are distinctively "glowy") but I wonder if the separation will continue. It's a 1937 copy, so I suppose this has been a slow process, but I wonder if it is like fungus and should be corrected as soon as possible.

 

[sanmich]

The good news: I finally found a reasonably priced Summar!
More good news: The glass is fairly clean.
The not-so good news: There is what I believe to be separation towards the front element. It goes all the way around the glass to a width of about a quarter inch. I took some test shots with it, and I can live with the resulting image characteristics (photos are distinctively "glowy") but I wonder if the separation will continue. It's a 1937 copy, so I suppose this has been a slow process, but I wonder if it is like fungus and should be corrected as soon as possible.

I had the same question (not a summar).
My conclusion was: degradation that takes more than a lifetime to reach a point that I can still live with are not fast enough for me to bother. The condition is either good enough or it isn't.
I asked focalpoint about a Summar repair (lots of tiny scratches) and it was a no-go. Too expensive for this lens, with serious chances of breaking everything.
Also, my totally uneducated guess about the glow that you see is that it has nothing to do with the limited separation that you discribed. Just the lens behavior (read "quality"😉)

 

[Sonnar Brian]

The Summar is a 1-2-2-1, 6 element in four groups. The front element is not cemented, so I suspect the separation is the cemented pair behind it?

I did a home repair of a separated pair on a 135/3.5 Canon RF lens using index matching fluid, like that for an oil immersion lens. 6 years later, still looks and works well.

 

[Steve M.]

The lens may be fine for years, and then again, not. Temperature changes make a difference, as when it's hot or cold the glass is contracting or expanding. Sudden changes are what you want to avoid. If it's winter and you head out the door into freezing weather it might not be a good idea.

 

[dogberryjr]

Here's what it looks like:

http://www.flickr.com/photos/dogberryjr/4956655333/in/photostream/

 

[jonmanjiro]

Here's what it looks like:

http://www.flickr.com/photos/dogberryjr/4956655333/in/photostream/

WOW 😱

I don't mean to be a stick in the mud or anything, but the separation is almost two-thirds of the surface. That lens is gone ....

 

[dogberryjr]

WOW 😱

I don't mean to be a stick in the mud or anything, but the separation is almost two-thirds of the surface. That lens is gone ....

Never say die! Look at what it produces even in this shape:
[url=http://www.flickr.com/photos/dogberryjr/4957463822/] Summar-1000087.jpg by dogberryjr, on Flickr[/URL]

 

[dogberryjr]

And another:

[/url]
Summar-1000086.jpg by dogberryjr, on Flickr[/IMG]

Color doesn't look so great, but I didn't really see this as a color lens anyway.