Focusing with 50mm Summicron

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New to Leica, being reading the posts in here and I must say I learned a lot. Anyway, I have this query: When focusing my summicron 50mm (current version) with my M6ttl 0.72, I found that when I am reaching the end of the focusing scale (0.7m side) there is a point where the image on the focusing patch will stop moving but I can still turn the focusing ring for a bit more (about 2 to 3mm more) before it reaches the stop point. That is I can still keep turning the focusing ring but the focusing patch image do not move for these last 2 to 3mm.

I have read somewhere that the image on the focusing patch should always follow the movement of the focusing ring. So, is there anything wrong with my camera/lens, or am I being paranoid?

Thanks a bunch guys.

-- J Yeo (ycy200@yahoo.com), March 16, 2001

Answers

You are being just slightly paranoid :-). It sounds like the close focusing limit on your camera needs to be adjusted. It is a very simple adjustment which should not take Leica (I assume it is under warranty) very long to do. Personally I would wait until there is a clinic at a local camera store and that way you will not be without your camera at all.

Cheers,

-- John Collier (jbcollier@home.com), March 16, 2001.


I've neve seen this happen with my 50's, or indeed with any focal length but my 21mm Super Angulon. The latter focuses closer than 0.7 meters (down to 0.4 meters, in fact). My impression is that the cam follower roller arm in the camera simply reaches the end of its travel at 0.7 meters. When the lens cam moves farther forward than that point, the arm is fully extended, so the rangefinder quits moving.

Based on that, I'd say the camera is adjusted corectly, since the arm does follow all the way to 0.7 meters. My guess is that it's the lens cam that's off. Maybe it's just a little too far forward at 0.7? I suggest trying it with another lens to compare. How's the infinity focus?

-- Bob Fleischman (RFXMAIL@prodigy.net), March 16, 2001.


I did it again. I spelled "correctly" incorrectly. We do need an intermediate screen to proofread.

-- Bob Fleischman (RFXMAIL@prodigy.net), March 16, 2001.

There is a simple adjustment that can be made, and should be made. Most Leicas are adjusted to focus down to about 0.6m...at least all of mine are (according to my 21 S/A which is marked past that point). The correct adjustment procedure requires taking off the plate that covers the shutter curtain adjustment in the bottom of the camera and the knockout plug the floor of the camera and inserting a precision driver up through to the adjustment eccentric next to the rangefinder follower. Unless you are well-equipped and "good with your hands" I strongly suggest leaving this to a trained repair person.

-- Jay (infinitydt@aol.com), March 16, 2001.

Thanks again for your inputs.:)

One thing I forgot to ask is, how would it affect my pictures, focus- wise. My 4R prints look ok, but I am no expert.

My infinity focus is spot on, the infinity symbol stops right at the central marker above the 2 on the Depth-of-field scala and the focus patch stops with it. However, my 0.7 marker focuses past the central marker above the 2 and comes to a stop at the f11 marker, is this normal? Does this mean that my 50 can focus to less than 0.7 metres??

Is there anyway to tell which setting is off (camera or lens)?

Sorry for troubling you guys with so many questions.

-- J Yeo (ycy200@yahoo.com), March 16, 2001.



Set a one meter ruler on the ground with the 50cm point marked with tape. With your camera at a 45 degree angle to the ruler, and about one meter away, choose the widest aperature you can, focus on the ruler at the tape and take a picture. Do this again at two meters. (Take a few pictures at each distance.) Process your film and you will immediately be able to see if your camera is under-focussing, over-focussing, or right on. If it is significantly off, send it in for adjustment. If it is on, don't worry any more about it, and just go out and take pictures!

-- Jack Flesher (jbflesher@msn.com), March 16, 2001.

Having too much time on my hands (and too much gear), I checked my lenses/cameras. My 35 Summicron, 50 Summicron and 75 Summilux all stop at .7 meters as does the RF patch on two different M6 bodies. My 35 Summilux-ASPH and 28 Elmarit focus past .7 by about 2mm on the lenses. The RF patch stops moving at .7 on both cameras. So, what gives?

-- Robert Schneider (robslaurat@earthlink.net), March 17, 2001.

Sounds right to me, that's consistent with what I get. But Jay seems to feel that the camera should track down closer to 0.6m. I'm not sure why.

-- Bob Fleischman (RFXMAIL@prodigy.net), March 17, 2001.

I am also new to Leica, having owned my M6 TTL .72 and 35mm summicron asph for all of one week. Camera and lens are about 8 months old and apparently in excellent condition. This thread led me to examine the 35 asph and I too found that the near focus adjustment goes 2 to 3 mm past the .7 mark - and the focussing patch moves with it. I seem to be able to focus down to about .62 meters but have not yet developed a film to see if I'm actually in focus at that point.

One question: when measuring the focus distance, is it to the front of the lens, the back of the lens, the film plane, or where?

Thanks.

-- Alan Shapiro (ashapiro@yorku.ca), March 17, 2001.


Alan:

Distance to the film-plane.

-- Jack Flesher (jbflesher@msn.com), March 18, 2001.



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