Help, loose front element on 9cm f/4 Elmar...

[physiognomy]

I just recieved a 9cm f/4 Elmar with some issues... It was a <$40 gamble from ebay , so I'm not too concerned, but the front element moves about! Is this going to be a problem? I'm assuming that if used wide open it might be an issue. One of the tiny screws on the front ring is missing, so I'm assuming that if I can find another screw it might be an easy fix...? I've attached a picture showing the front element off center... with a few gentle taps I can get it back to a normal position.

The lens also seems to have some 'haze' on the inside of the 2nd element... When I screw off the front there is a brass ring holding this lens on... Do I just remove this to get access to the inside lens surface?

Any advice would be appreciated.

Peter

 

[back alley]

photo?


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[physiognomy]

photo?

Thanks for catching that Joe... Doing too many things at once...

Peter

 

[physiognomy]

No one has played with one of these?

Peter

 

[VictorM.]

It would seem almost impossible for the front element to move around because it sits (tightly) in a recess. On top of the lens is a circle of what seems like thin cardboard-it's probably to protect the lens from the retaining ring. The retaining ring is screwed down on the element so the cardboard ring is trapped in a recess-the flat side of this retaining ring faces outward. The trim ring, with the identifying words/numbers, screws in last. It doesn't really have anything to do with holding the front element in place. Your lens seems to have the cardboard ring floating around. Should be an easy fix.

 

[physiognomy]

Hey Victor,

Thanks for your help! I reallly appreciate you posting those pictures and giving me some diagnosis... I guess I didn't look at the lens close enough, but it definitely could be the cardboard disk you mention & not the whole element floating around in there... Does that mean the retaining ring must be loose as well? Hopefully it just needs to be tightened a little... If the screws just hold the trim ring on I shouldn't need to search out a replacement for the one that is missing?

From your picture the front retaining ring looks very similar to the one on the back of the front elements... hopefully removing this will help me clean up the haze issue...

Thanks again for all your help!

Peter

 

[VictorM.]

Here's the rear elements removed. The lens elements are a slip fit into the barrel and should be easy to remove after you remove the retaining ring. Similarly, the front element should pop out when you remove the retainer. Be very careful (gentle) when cleaning the haze because the inner surfaces are easily scratched. Also, when removing the front trim ring, don't stick anything metal in the tiny screw holes; you'll ruin the threads. I used a toothpick to gently push the ring loose (after removing the screws). Don't remove the two screws on the aperture ring; the blades will fall out.

 

[physiognomy]

Thanks again for all your helpful advice Victor! Late last night I got together some 'tools' & fixed the problem with the loose retaining ring... It was barely screwed on, so no wonder the 'protection' ring was floating around in there! My compass wasn't strong enough to remove the retaining ring on the rear of the first elements, so the haze is still present... Hopfully I'll get to that problem sometime soon... I attached some pictures of this minor surgery... I was amazed by the intricacy of the aperture blades!

Regards,

Peter