jbl Posted July 29, 2015 Share #1 Posted July 29, 2015 Advertisement (gone after registration) I've read several threads on this, but I haven't fully understood how hard it is to do a rangefinder adjustment on the M246. Coincidence at infinity is not an issue, I've had that on one of my film M's and I know what that looks like. The camera is back focusing and what I'm noticing is when I focus on my son's eye (he's five months) I'm slightly off and the focus is closer to his ear. I ran some tests last night on a tripod and I'd guess it's off in the 1/2 inch to 1 inch range at the near focusing distances, I'm definitely seeing it in the 0.7m-2m range and I think I've seen it in the 5-10m range. If someone who knows how to do this could help me a bit on it, that'd be really helpful. Or I'll just send it to New Jersey but I'd prefer to avoid a multi-week trip. Thanks! Quote Link to post Share on other sites More sharing options...
Advertisement Posted July 29, 2015 Posted July 29, 2015 Hi jbl, Take a look here Adjusting the rangefinder. I'm sure you'll find what you were looking for!
jaapv Posted July 29, 2015 Share #2 Posted July 29, 2015 Adjustment of the rangefinder as such is doable, there are a couple of threads on the forum, BUT on a digital M one must make sure first that the sensor is correctly aligned to 1/1000th of a mm. I think only Leica can do that. Quote Link to post Share on other sites More sharing options...
bocaburger Posted July 29, 2015 Share #3 Posted July 29, 2015 (edited) I had to do a complete rangefinder adjustment on my M9, it's not brain surgery but it does require patience and care. Questions before proceeding: 1. Is this your first digital M body, i.e.have you used your lenses before on an M9 or MM and they were fine? 2. Does this happen equally with more than one lens? 3. Have you checked infinity coincidence on a subject at least a mile away? Such as a distant TV tower, or the edge of the moon, or a crisply-detailed cloud? Edited July 29, 2015 by bocaburger Quote Link to post Share on other sites More sharing options...
Jeff S Posted July 29, 2015 Share #4 Posted July 29, 2015 (edited) Some discussion here… http://www.l-camera-forum.com/topic/221313-rf-focus-adjustment-required/ I presume you've used LV to help assess the issue….as well as compared different lenses. Jeff Edited July 29, 2015 by Jeff S Quote Link to post Share on other sites More sharing options...
thighslapper Posted July 29, 2015 Share #5 Posted July 29, 2015 (edited) I've read several threads on this, but I haven't fully understood how hard it is to do a rangefinder adjustment on the M246. Coincidence at infinity is not an issue, I've had that on one of my film M's and I know what that looks like. The camera is back focusing and what I'm noticing is when I focus on my son's eye (he's five months) I'm slightly off and the focus is closer to his ear. I ran some tests last night on a tripod and I'd guess it's off in the 1/2 inch to 1 inch range at the near focusing distances, I'm definitely seeing it in the 0.7m-2m range and I think I've seen it in the 5-10m range. If someone who knows how to do this could help me a bit on it, that'd be really helpful. Or I'll just send it to New Jersey but I'd prefer to avoid a multi-week trip. Thanks! Easier than the M9. You have live view as a comparison and the RF images are crisper so it is easier to gauge the focus point. Only other difference is some sort of loctite on the near adjustment mechanism locking screw ..... needs softening a little with acetone/butanol or similar to get it to unscrew. Reseal it the same way when finished. There is a very comprehensive thread with info by Julian Barnes on the principles and practicalities of doing it ....http://www.l-camera-forum.com/topic/118043-m9-coincidence-at-infinity/ If you are careful, don't scratch the adjustment points and reseal the locking material on the screw no-one will know you have tampered with it ...... so you are unlikely to invalidate your warranty even if you fail miserably to get it right and have to send it in ....... Be aware that changes to the near point adjustment tend to put the infinity point off ..... and vice versa ..... but if the near point adjustment is small (which from your description it will just need a nudge) then the infinity point may need nothing at all..... and anyway it's just a tweak with a allen key that takes seconds. It can be difficult to tighten the locking screw without the adjuster moving a bit ...... which I suspect is why a few cameras escape without being absolutely spot on. Edited July 29, 2015 by thighslapper Quote Link to post Share on other sites More sharing options...
jbl Posted July 29, 2015 Author Share #6 Posted July 29, 2015 I had to do a complete rangefinder adjustment on my M9, it's not brain surgery but it does require patience and care. Questions before proceeding: 1. Is this your first digital M body, i.e.have you used your lenses before on an M9 or MM and they were fine? 2. Does this happen equally with more than one lens? 3. Have you checked infinity coincidence on a subject at least a mile away? Such as a distant TV tower, or the edge of the moon, or a crisply-detailed cloud? It is not my first M body. I've had the M9, MM and two M240s. I presently have an MM, an M240 and the M246. There's definitely a difference between this body and the others. I've seen it with many different lenses, all three 50mm summiluxes and all three noctiluxes. I mostly notice it at f/1.4 and larger which is what I would expect. I will double check infinity coincidence tonight. -jbl Quote Link to post Share on other sites More sharing options...
Guest JMF Posted July 29, 2015 Share #7 Posted July 29, 2015 Advertisement (gone after registration) It is not my first M body. I've had the M9, MM and two M240s. I presently have an MM, an M240 and the M246. There's definitely a difference between this body and the others. I've seen it with many different lenses, all three 50mm summiluxes and all three noctiluxes. I mostly notice it at f/1.4 and larger which is what I would expect. I will double check infinity coincidence tonight. -jbl This thread has all the infos and diagrams: http://www.l-camera-forum.com/topic/118043-m9-coincidence-at-infinity/ I refer to it often ! Quote Link to post Share on other sites More sharing options...
jbl Posted July 29, 2015 Author Share #8 Posted July 29, 2015 That helps a lot, thanks. Am I reading it correctly that if infinity is off, that may explain the back focusing up close? But if infinity is not off, the screw needs to be loosened to adjust the cam? Can someone tell me a bit more about the lock in the cam screw and if you need to modify a screw driver? Quote Link to post Share on other sites More sharing options...
Jeff S Posted July 29, 2015 Share #9 Posted July 29, 2015 See the link provided twice above….including post #15. Jeff Quote Link to post Share on other sites More sharing options...
jbl Posted July 29, 2015 Author Share #10 Posted July 29, 2015 Thanks. I read that thread and it's very helpful, but I'm still not sure under what circumstances both pieces need to be adjusted. Is it always? Quote Link to post Share on other sites More sharing options...
rapids41 Posted July 29, 2015 Share #11 Posted July 29, 2015 Yes. 2) Take a photo at a big aperture of something close to you - like 0.8 meters or similar. I found text to be excellent. Note whether you now have front focus or back focus. If you have front focus (like I did - big time!) then your focus throw is too short; ie your arm is too long, so when the lens rotates you're not pushing the rangefinder enough. So you need to shorten the arm by loosening (A) and twisting the cam slightly anti-clockwise. (If you have backfocus then it's obviously the inverse and you need to go clockwise to lengthen the arm and reduce your focus throw). 3) Now, recheck infinity. It will now be wrong, because you have now moved the arm and so the roller wheel has also moved. But this is not a problem - just recorrect infinity as in 1) above to compensate for the altered focus throw. After that repeat step 2 and 3. Quote Link to post Share on other sites More sharing options...
Jeff S Posted July 29, 2015 Share #12 Posted July 29, 2015 I mentioned post #15 in the link because of your second question regarding the screwdriver. Jeff Quote Link to post Share on other sites More sharing options...
jbl Posted July 29, 2015 Author Share #13 Posted July 29, 2015 Thanks, Jeff. Can you file a screwdriver down with coarse sandpaper or do I need a metal file? Quote Link to post Share on other sites More sharing options...
Jeff S Posted July 29, 2015 Share #14 Posted July 29, 2015 Sorry, no idea…I would never attempt the adjustment. But I'm pretty good with the search function. I've received quick turnaround on all service with Leica NJ, always with an advance call to a rep to coordinate communications and timing. They have better tools and expertise, especially in the digital age. And my back-up M8.2 works fine if needed. Jeff Quote Link to post Share on other sites More sharing options...
jbl Posted July 30, 2015 Author Share #15 Posted July 30, 2015 Did some checks just now. Using LV, near focus is barely off. At 5x, I can't see it. At 10x it's slight. I went outside and infinity doesn't quite converge. So does that mean both adjustments are off? Quote Link to post Share on other sites More sharing options...
Jeff S Posted July 30, 2015 Share #16 Posted July 30, 2015 (edited) LV is of course exactly what the sensor 'sees'…..how does the RF compare….with each lens…at different apertures…and distances? (And note that some lenses exhibit focus shift when stopping down….separate issue). If you then suspect RF is off at infinity… http://www.l-camera-forum.com/topic/244454-rangefinder-slightly-off-at-infinity/ Jeff Edited July 30, 2015 by Jeff S Quote Link to post Share on other sites More sharing options...
jbl Posted July 30, 2015 Author Share #17 Posted July 30, 2015 I spent a bunch more time last night looking into it further, especially once the moon came up. What I'm seeing is this: During the day, sitting on one side of my street and focusing on my neighbor's house address number, the lenses end up at infinity. The distance is less than 100m. My understanding is at that distance, it should be nearer than infinity. Later, I focused on the full moon and I think it the split image came together at infinity. At least to the ability of my eye site which according to an eye exam a few months ago, close to perfect. I tried it both with and without the 1.4x magnifier. I tried later indoors with focusing on some books on my book shelf in the 0.7-1m range and it's very, very sightly off. From those examples, I could live with it, but I seem to be missing focus slightly on my son's eyes when I focus on them, so I'm sort of at a loss of what to do. It seems off at infinity by using my neighbor's house as an example, but it seems to be on when using the moon. -jbl Quote Link to post Share on other sites More sharing options...
Jeff S Posted July 30, 2015 Share #18 Posted July 30, 2015 You didn't answer my question. Jeff Quote Link to post Share on other sites More sharing options...
jbl Posted July 30, 2015 Author Share #19 Posted July 30, 2015 Sorry. I've tried the infinity coincidence with two lenses (50mm Summilux ASPH and v2 pre-ASPH) and I've seen the focus errors in actual use with all three Summiluxes and all three Noctiluxes. Infinity coincidence seemed the same with both lenses I tried with it. I tried the live view test with a single lens, but I can easily try it with another lens. -jbl Quote Link to post Share on other sites More sharing options...
Guest JMF Posted July 30, 2015 Share #20 Posted July 30, 2015 (edited) jbl, run a few tests at minimum distance, mid and infinity ( lens wide open obviously and at a good fast shutter speed ) shooting with the RF and live view then compare the results on a large screen , not the camera LCD . Also stay square in front of the chart / subject , not at an angle. Then try firstly to adjust the infinity "B" roller very calmly and gently according to post #15 above. If you don't get satisfying results, visit a camera RF specialist ! Don't go into the screwdriver filed at an angle etc, it gets fiddly and does require expertise to do it with no harm to your camera. Try get involved with the camera person and learn from that person first. My 2 cents, JM. Edited July 30, 2015 by jmanivelle Quote Link to post Share on other sites More sharing options...
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