Lens to Rangefinder Adjustment

dazedgonebye

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I've got a CZJ Werra with the three interchangeable lenses. I've been working on adjusting the rangefinder...which I believe I've not got right. The problem is that, although the 50mm and 100mm lenses look to be right, the 35mm lens is not.

I adjusted the rangefinder with the 50mm on, using a ground glass at the film plane to verify the rangefinder. The 100mm looks good at the same adjustment.
The 35mm though has to be focused to infinity (using the focus scale) before it is on at 5 feet away.

Forgive my terminology, I'm learning this from scratch...

Looking at the back of the three lenses when they are focused to infinity, I noticed that the optical units of the 50mm and 100mm are slightly recessed from the rear of the lens mount. The 35mm optical unit extends just beyond the rear of the lens mount.

From this, I'm concluding that there must be some adjustment possible to the lens. Unfortunately, I have no idea how to accomplish this.

Help...:bang:
 
The fact that the optical unit on the 35 extends backwards would not be unusual for a wide angle. However, I would aggree with you that the problem is likely to be the 35 lens. If I understand you correctly, if the 35 lens is set to infinity, then the plane of focus is 5 feet away. If so, it would indicate the whole lens group should be nearer the body.

Kim
 
Kim Coxon said:
The fact that the optical unit on the 35 extends backwards would not be unusual for a wide angle. However, I would aggree with you that the problem is likely to be the 35 lens. If I understand you correctly, if the 35 lens is set to infinity, then the plane of focus is 5 feet away. If so, it would indicate the whole lens group should be nearer the body.

Kim

The lens group may need to be further back...but the part of the lens that contacts the rangefinder coupling is already so far back that the rangefinder indicates infinity almost all the time.
Somehow, that back plate must move forward relative to the lens group. I just don't see how (and I've got a real fear of tearing this lens down).
 
There is an instruction on the net somewhere how to open the lens and do the adjustments. maybe in german. I have a print out somewhere but dont ask where i should search for it in my papers. maybe i will find on my pcs. rather unlikely since its old stuff.
informations:
http://www.kyphoto.com/classics/forum/messages/6899/6058.html
pdf-files are missing.
adjusting the lens is only for experts. i remember the procedure to be very complicated.
 
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