farlymac
PF McFarland
When I got my 1951 Summitar 50/2 the aperture would go from very loose to very stiff and back again. Didn't seem to matter what I did with it, even loosening up the optical block a bit to see if it was binding there.
Eventually I took the block out to get a look at the workings of the aperture and saw something I'd never experienced before. The aperture blades form a dome when at f16.
Anyway, they are extremely stiff now, and I'm worried something might be bent. I don't see any spacing issues such as you would expect if one of the blades were broken. I'm a little reticent to take the retainer out as I don't want them to go flying.
Any word on what could be causing this binding issue? It can't be the retainer because the set screws have it firmly locked, and the aperture started out as being loose.
PF
Eventually I took the block out to get a look at the workings of the aperture and saw something I'd never experienced before. The aperture blades form a dome when at f16.
Anyway, they are extremely stiff now, and I'm worried something might be bent. I don't see any spacing issues such as you would expect if one of the blades were broken. I'm a little reticent to take the retainer out as I don't want them to go flying.
Any word on what could be causing this binding issue? It can't be the retainer because the set screws have it firmly locked, and the aperture started out as being loose.
PF
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shawn
Veteran
Did you clean under the ring that you twist to actuate the aperture? That is where mine was binding. Not in the assembly itself.
Shawn
Shawn
brusby
Well-known
It's most likely dried lubricant on either the outer aperture ring or on the blades and supporting mechanism, or both. The former is pretty easy to clean and replace. But if you take the blades out to clean them, it will be a real chore to get them back in correctly.
farlymac
PF McFarland
Haven't done any cleaning yet, though there is some haze that needs to be removed.
brusby said:
Yeah, really wanting to avoid that. Weather is supposed to turn nasty on Tuesday so I'll give the ring a clean and lube then.
PF
farlymac
PF McFarland
Success! Checked a video on U-Tube as to take the aperture ring off (of course it was of the older version) so I wouldn't mess up the aperture blades. Took about fifteen minutes, and it now works like a charm.
That is the first time I've ever seen aperture blades designed to form a dome which is quite an experience in itself. I was originally afraid they were binding which caused the doming.
I took the opportunity to clean the interior elements since they were a little hazy. Now have to wait for the weather to clear up again before taking it on a test drive. Thanks, Shawn and Brusby for the help!
PF
That is the first time I've ever seen aperture blades designed to form a dome which is quite an experience in itself. I was originally afraid they were binding which caused the doming.
I took the opportunity to clean the interior elements since they were a little hazy. Now have to wait for the weather to clear up again before taking it on a test drive. Thanks, Shawn and Brusby for the help!
PF
brusby
Well-known
Congrats, it's a terrific lens. I recently posted some photos made with the same version and same year you have.
https://www.rangefinderforum.com/forums/showthread.php?t=172882&highlight=Summitar
https://www.rangefinderforum.com/forums/showthread.php?t=172882&highlight=Summitar
farlymac
PF McFarland
I shot a roll with it last year (not developed yet) on the Bessa-R, so will be able to make a comparison pre and post cleaning. I got brave and looked up how to open an Elmar 50/2.8 (why does Leica always have to change the basic design with every lens?), but I don't hold out much hope for that one. The front element is very scratched, the haze on the inside wouldn't come off, plus a bit of fungus I wasn't able to get to for lack of the proper lens tools.
Those were some lovely shots you got with your lens.
PF
shawn
Veteran
If you figure the Elmar 2.8 is a goner get some "GP14004 Fine Grade Glass Polishing Compound" from Amazon. Use it to lightly polish the hazy element and you might save it. Practice on a junk lens if you have one.
Shawn
Shawn
farlymac
PF McFarland
Man, I've got a box full of junk lenses, but most of them are for SLR's so it wouldn't be like handling one of these tiny rangefinder lens elements. I'll keep that in mind though if I decide to give it another go.
PF