[Konvas] Lens question...

[Adam Frey]

My Foton 37-140mm lens looks like it has seen better days and is in  
need of servicing. I'll describe the issues:

1) it has a "circle" on the front element (inside). That's my biggest  
issue.
2) it's a little sloppy. Not horribly sloppy, just a little play when  
changing direction when focusing. I'd rather it was 100%.
3) it's a little tight.

So it most likely needs a good servicing & cleaning.

Has anyone had the audacity to crack one of these open for cleaning?  
Since it's a zoom, I am afraid to crack it open. I remember we talked  
about that last year - and I remember someone saying that zooms were  
much harder to do on your own and best left to a professional.

The circle is not something I've seen before on other lenses. But can  
anyone tell me if they've seen this issue before? I think it looks  
like grease which has somehow dripped down onto the backside of the  
front element. If you look at the 2nd (darker) image lower right  
corner of the lens, you can see what looks like a grease dripping spot  
(like a Q with a bar at the end), then the lens could have been  
rotated and subsequently created the circle or some such (not sure).  
I'm hoping it's not a glued front element coming undone.

Should I send it out for servicing or just not even waste my time and  
sell it as is? The lens looks like will do 37-100mm wide open and  
without too much issue. It will also go all the way out to 140mm, but  
at about f8 without noticing the circle. But this is with my own eye  
plugged right up to the back and looking thru it, since I don't have  
my Konvas nearby at this moment - meaning the film distance could make  
it more - or less - critical. So it might even be able to get away  
with it zoomed in tighter and/or more open, but probably not.

I bought this lens last year to use for the full gamut, and I can work  
around the limitations if needed (just switch out with a few other  
lenses when tele is necessary) - but I'd rather not deal with any  
limitations. The lens is kinda slow and already limiting me enough...

BTW: Who else on the list owns this lens?


Adam Frey
Director/Cinematographer
Crimson Chain Productions
http://crimsonchainproductions.com

"Time is an aggravating foe."


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