viramati Posted July 6, 2013 Share #1 Posted July 6, 2013 Advertisement (gone after registration) With just over a couple of months of use I have discovered that my M is out of calibration and in fact back focussing quite a bit. At first I thought it was just a problem with the CV nokton 35 1.2 but now I find (having got my tripod back from a friend) that the lux 50 asph. 90 elmarit-M and 135 apo-telyt are all out. I'm sure it wasn't this bad a week or so ago but I had begun to notice I was having more problem hitting focus wide open and even stopped down foregrounds were not as they should be. All the lenses were calibrated along with one of my M9's last november and still seem fine on that camera. Anyway to cut to the chase the thought of another month or so with having to send it all back to Solms really has me hacked off so I was wondering that now that we have our own in house calibration system in the form of live view if it maybe easier to do a DIY calibration. though I probably won't attempt it due to warranty issue etc I wondered what anyone who already has the M thought about this. As a PS out of 4 digital M's I have owned only 1 came out of the factory correctly calibrated!!!! 1 Quote Link to post Share on other sites More sharing options...
Advertisement Posted July 6, 2013 Posted July 6, 2013 Hi viramati, Take a look here M (240) calibration. I'm sure you'll find what you were looking for!
Lindolfi Posted July 6, 2013 Share #2 Posted July 6, 2013 David, most likely the eccentric bolt of the rangfinder roller just needs a nudge, using an allan key. Look in the forum for instructions, for instance here: http://www.l-camera-forum.com/leica-forum/customer-forum/196861-adjusting-vertical-alignment-your-self.html#post1807390 With the EVF it has become a lot simpler: you don't need "infinity" anymore. Quote Link to post Share on other sites More sharing options...
viramati Posted July 6, 2013 Author Share #3 Posted July 6, 2013 Thanks Bert. So if the camera is focussing very slightly behind (I'm focussing on objects in the 1-3metre range) which way should I be trying to turn the wheel Quote Link to post Share on other sites More sharing options...
Lindolfi Posted July 6, 2013 Share #4 Posted July 6, 2013 If I remember correctly, if you insert the allan key with the handle sticking to the left when standing behind the camera, moving the handle forward shifts the real focus forward at the correct overlap in the rangefinder. So in your case you would have to move the key backward slightly. You need a few iterations and you will have to get a feel for the elasticity of the allan key and the friction of the hex bolt so that you push just through the friction. Anyway, it is worth trying it. Quote Link to post Share on other sites More sharing options...
120 Posted July 6, 2013 Share #5 Posted July 6, 2013 (edited) If I remember correctly, if you insert the allan key with the handle sticking to the left when standing behind the camera, moving the handle forward... ? To move the focus forward turn the Allen key CCW? Thanks Edited July 6, 2013 by 120 Quote Link to post Share on other sites More sharing options...
Lindolfi Posted July 6, 2013 Share #6 Posted July 6, 2013 if you have the camera in normal orientation (top plate up) and you look from below upward, you turn the allan key counterclockwise to move the focus away from the camera at correct overlap in the rangefinder. 1 Quote Link to post Share on other sites More sharing options...
120 Posted July 6, 2013 Share #7 Posted July 6, 2013 Advertisement (gone after registration) if you have the camera in normal orientation (top plate up) and you look from below upward, you turn the allan key counterclockwise to move the focus away from the camera at correct overlap in the rangefinder. I was just wondering about this yesterday. Not having done the adjustment, can you turn this more than half-way around and then the focus goes the other direction? Also, what is the setup at the pivot end of the roller arm; what exactly are you turning to change the arm length? And I also wanted to know what is "upstairs." How does the pivot of arm A (roller arm) contact arm B with the deflection element upstairs? Arm B is pivoted at the deflection element, and the other end of B follows a cam on the pivot of A? thanks! Quote Link to post Share on other sites More sharing options...
Lindolfi Posted July 6, 2013 Share #8 Posted July 6, 2013 The roller has an eccentric bolt, so you just move the roller forward or backward, providing an offset of the action of the rangefinder. Just a bit is sufficient, you don't need to turn it full or half circle The slotted bolt at the base of the rangefinder arm changes the length of the arm (by an eccentric cam), thereby changing the gain of the movement of the rangefinder mechanism. Quote Link to post Share on other sites More sharing options...
thighslapper Posted July 6, 2013 Share #9 Posted July 6, 2013 (edited) The eccentric roller moved with the allen key is the infinity adjustment. It will alter near focus, but that is not what it is meant for..... You MUST check what is going on at infinity first ....... and adjust this so it is correct (best lens to use is a 75 or 90) If images are aligned in the finder at infinity then fiddling with the roller will just cause more problems. ........ any adjustment of the infinity roller puts the near point focus off .... and vice versa ...... The next bit is where you either go for it or chicken out ...... playing with the screw that holds the near point adjuster Full adjustment is not difficult, but fiddly and a bit confusing until you get the hang of it.... Infinity roller adjustments are usually tiny ..... just a nudge ...... near point arm adjustments need to be quite a bit more to have a significant effect. I've now done it half a dozen times and the last time with my errant MM took half an hour .... it would have been quicker but I have to go repeatedly upstairs to get a view of a pylon 2km away to use as infinity... The link here explains it all..... just be patient and careful... http://www.l-camera-forum.com/leica-forum/leica-m9-forum/122176-m9-coincidence-infinity.html Live view will only confirm your suspicions that things are out ....... realistically it is not going to help in rangefinder calibration ...... it's still going to be a process of fiddling and head scratching... Edited July 6, 2013 by thighslapper Quote Link to post Share on other sites More sharing options...
120 Posted July 7, 2013 Share #10 Posted July 7, 2013 The roller has an eccentric bolt, so you just move the roller forward or backward, providing an offset of the action of the rangefinder. Just a bit is sufficient, you don't need to turn it full or half circle The slotted bolt at the base of the rangefinder arm changes the length of the arm (by an eccentric cam), thereby changing the gain of the movement of the rangefinder mechanism. Thanks. Can you say how the two lever arms contact each other...for someone who has not disassembled the camera, or found a decent diagram? How does the one arm swing backwards as the roller arm swings forwards? Apparently the gain adjustment in the Leica II/III is effected at the roller end of the roller arm, and the offset (infinity) adjustment at the other lever arm. In this camera, too, I am wondering how the two lever arms contact each other. It looks like there may be a little shaped cam at the end of the "shaft" (achse) the roller arm pivots with. ??? Quote Link to post Share on other sites More sharing options...
Lindolfi Posted July 7, 2013 Share #11 Posted July 7, 2013 (edited) There is only one lever arm. Here you can see the parts: So the roller has an eccentrically placed bearing which can be turned using the hex bolt and there is a little cam underneath the base bolt that changes the length of the arm, which is mounted to the axis through a slotted hole. Edited July 7, 2013 by Lindolfi 1 Quote Link to post Share on other sites More sharing options...
viramati Posted July 7, 2013 Author Share #12 Posted July 7, 2013 Thanks Bert for your advice and pointers. For once something useful on the forum. the minutest tweak with the allen key seems to have corrected the problem (even the 135 is now correct!!). Will always keep one in the camera bag from now on. Quote Link to post Share on other sites More sharing options...
120 Posted July 7, 2013 Share #13 Posted July 7, 2013 There is only one lever arm. Here you can see the parts: ... here is what you said last last time around, "If you look at the turning angle of the element with the tiny lens, it is less than the turning angle of the rangefinder arm. That has to do with the longer lever arm on the element with the tiny lens than the one on the rangefinder arm axis, that is in contact with that longer lever arm," i.e. two lever arms. I am asking, what is the mechanical arrangement to get from one thing (the turning of the roller arm on its pivot) to another (the turning of the other part on its pivot)? Quote Link to post Share on other sites More sharing options...
Lindolfi Posted July 7, 2013 Share #14 Posted July 7, 2013 (edited) I am asking, what is the mechanical arrangement to get from one thing (the turning of the roller arm on its pivot) to another (the turning of the other part on its pivot)? Terribly sorry for not having answered your question the way you wanted it. Hopefully this is helpful: 1) The roller is pushed by the lens cam 2) This turns the arm that is visible when you look in the camera 3) The axis to which this arm is attached has a rotating cam in the body of the camera 4) This cam pushes against a hookshaped arm that is attached to another axis 5) This hookshaped arm is spring loaded 6) This hookshaped arm also is attached to a small lens carrier that rotates with the arm 7) This rotation of the small lens moves the light coming form the secondary rangefinder window Hope this is to your satisfaction. If not I can make a movie of the whole process. Edited July 7, 2013 by Lindolfi 1 Quote Link to post Share on other sites More sharing options...
120 Posted July 7, 2013 Share #15 Posted July 7, 2013 ... So the roller has an eccentrically placed bearing which can be turned using the hex bolt and there is a little cam underneath the base bolt that changes the length of the arm, which is mounted to the axis through a slotted hole. I got the one adjustment as soon as you said "eccentric bolt." I got the other adjustment only after seeing the photo of the ridge at the end of the roller arm; I would call this one an eccentric washer pushing against a ridge, if I understand it correctly. Thanks... Quote Link to post Share on other sites More sharing options...
120 Posted July 7, 2013 Share #16 Posted July 7, 2013 Terribly sorry for not having answered your question the way you wanted it. Hopefully this is helpful: 1) The roller is pushed by the lens cam 2) This turns the arm that is visible when you look in the camera 3) The axis to which this arm is attached has a rotating cam in the body of the camera 4) This cam pushes against a hookshaped arm that is attached to another axis 5) This hookshaped cam is spring loaded 6) This hookshaped arm also is attached to a small lens carrier that rotates with the arm 7) This rotation of the small lens moves the light coming form the secondary rangefinder window Hope this is to your satisfaction. If not I can make a movie of the whole process. Thanks Bert! Have been looking for #3,4 for some time. So that is interesting if both cam 3 and arm 4 are specially shaped to get the turning of the arm just right. (I have this correct?) In the original 30's design, and I think Leica II/III also, there is just one cam shape to work out (which the "prism arm" follows). No need for a movie, but thanks very much for the info, which as far as I know is not available elsewhere. Quote Link to post Share on other sites More sharing options...
Rick Posted July 7, 2013 Share #17 Posted July 7, 2013 (edited) Bert, I don't know how others feel about this but, Movie, please. :) This would make a great sticky. Maybe even an uber-sticky! Edited July 7, 2013 by RickLeica 1 Quote Link to post Share on other sites More sharing options...
Lindolfi Posted July 7, 2013 Share #18 Posted July 7, 2013 (edited) Here is the movie (shot with the M (typ 240) and a Schneider Kreuznach 135/5.6 lens at f/16) http://www.photoplaza.nl/lindolfi/L1009413four.MP4 The moving part at the most right hand side is the cam on the axis of the range finder arm. It has a certain rounded (calculated) shape. It pushes against the hookshaped arm that has a flat section to which the cam pushes. You can see the spring that loads the hookshaped arm under the contact of cam and arm. Straight above the roller to which I push, you can see a shiny ridge. That is the frame that holds the frame lines that move upward to correct for parallax. The most left hand moving part is the house that contains the small lens passing the image from the secondary rangefinder window to the eyepiece. Edited July 7, 2013 by Lindolfi 9 Quote Link to post Share on other sites More sharing options...
k-hawinkler Posted July 7, 2013 Share #19 Posted July 7, 2013 Bert, Many thanks to a courageous man! Quote Link to post Share on other sites More sharing options...
viramati Posted July 7, 2013 Author Share #20 Posted July 7, 2013 loving the movie 1 Quote Link to post Share on other sites More sharing options...
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