luigi bertolotti Posted November 13, 2009 Share #21 Posted November 13, 2009 Advertisement (gone after registration) ...would be interested to know if they have this in NJ as well. I heard second-hand (from this forum) they used to test lenses with a wall chart, hand-held, and I always wondered if that was really true. For what I remember from the pics, I'd say no... it was a system clearly engineered to make number of calibrations within the context of a "rolling" production line... labs that make such work "on demand" probably use less automated gear. Link to post Share on other sites More sharing options...
Advertisement Posted November 13, 2009 Posted November 13, 2009 Hi luigi bertolotti, Take a look here M9 Focus/Rangefinder Calibration. I'm sure you'll find what you were looking for!
hoppyman Posted November 13, 2009 Share #22 Posted November 13, 2009 considering how few cameras seem to be out there- and how many contributors seems to have this problem- it is a little concerning to say the least. In that Leica factory video of the M9 production they show the calibration of the focus at the factory on the line- and it seems rather thorough. It is concerning that the focus can seemingly move out of alignment so easily? I hope standards on the line haven't dropped with with the increasing output? Jaques, I think it would be a mistake to come to any conclusions based on a few posts which represent a very small sample. Here's a shot from mine anyway Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/103492-m9-focusrangefinder-calibration/?do=findComment&comment=1116047'>More sharing options...
Alnitak Posted November 13, 2009 Author Share #23 Posted November 13, 2009 I do not think that error is worth sending it back. First of all that is not a large error, and it's an error to the front, so it will be cancelled out by reframing and the attendant error. In case you used the usual chart; this is great for giving you some idea that you're off from the standard, but you certainly can't tell the error to the millimeter as suggested. I think you would be lucky if the accuracy of this kind of test is to the centimeter; there is variation from your eye position, from play in the rangefinder mechanism, reading of the chart, etc. I bet a very large percentage of cameras and lenses get sent back to Leica that are perfectly in spec. On the other hand, it is important to test your lenses or have it done, and it sounds like you did a good job with it. I used millimeters because this forum has a large non-American contingent; it was an approximation. That said, it's a pretty close approximation so I felt comfortable typing it, and yes, you CAN easily tell how accurate the rangefinder is to about the millimeter level. Tripod-mount the camera, use a magnifier to help with precise focus, and then take a series of focused shots for a good sample of consistency/repeatability. In my case I did this with nearly all of my lenses, and the camera consistently front-focuses by 1/2 inch or 12-13mm. Very consistently. While that may not seem a significant error, I assure you it is. It's the difference between the eyes and the tip of the nose being in focus when shooting most of my lenses wide open. Because I shoot a lot of portraits and typically shoot wide open, and frequently at the minimum focus difference, the 1/2 inch front focus is a killer. With my M8.2 I can nail 90% of the shots in this situation with very precise focus where I want it. With the M9, I am getting great focus on the tips of noses. If I liked noses more, that might be a great thing, and even though I don't dislike noses, in a portrait its the eyes we generally want to see in focus. Anyway, the M9 is boxed up and going to Leica repair Monday morning. I called and spoke with the repair staff and they said they could turn it around quickly knowing the situation. Hope they are right! Jeff Link to post Share on other sites More sharing options...
arnold kaufman Posted November 14, 2009 Share #24 Posted November 14, 2009 JeffI I dont know if I understand what front focusing means exactly.Are you saying when as an example you set the 75 cron at f-2.0 & focus to 0.7 m the image is not in focus or is there something else going on. Earlier this week I purchased a 75 cron & have had great sucess shooting different subjects, however not @ 0.7 m but wide open.How does one test for front focus? I am using a M-9 & have a M8.2 as a back up. Any info would be appreciated. Arnold Link to post Share on other sites More sharing options...
Alnitak Posted November 14, 2009 Author Share #25 Posted November 14, 2009 Arnold, Think of this way. Let's say I used the 75 'cron, and set the lens at 0.7m. I then set a target at exactly 0.7m from the focal plane of the camera. If everything is calibrated correctly, the rangefinder patch will show the target perfectly focused, and the image will be in perfect focus. If the rangefinder is front-focusing, it will show the target as being out of focus, even the image will be in perfect focus. If I moved the camera back away from the target, a front-focusing rangefinder (or rather, one that is calibrated to the wrong distance relative to the true focal point) will show now show the image as being in focus in the rangefinder patch, but the real focal point of the image would be in front of the target, and the image will show that by being out of focus. Another way to think of it is if the target is at 0.7m, and the lens is set at 0.7m, and the image is in perfect focus, then the front-focusing rangefinder will think that the target is really at 0.71m. Now, this can be caused by the lens being out of calibration as well. One way to tell if its the lens or the camera is to try it with different lenses. If they all show a consistent misfocus in the same direction, then its the rangefinder. If just one lens shows a problem, then its the lens that is out of calibration. The f-stop matters because of course it affects the DOF. The DOF for the 75mm 'cron on an M9 at 0.7mm is only 9mm. If the rangefinder is calibrated to have the focus point exactly precise (and Leica claims millimeter-precise alignment), then I have just a few mm in front of and behind the target that will be in focus. That's why being off my 12-13mm, which is my case, is a big problem. That means that the entire target is out of the DOF zone, and is totally blurry. Or, the eyes are out of focus, but the tip of the nose looks great. Jeff Jeff Link to post Share on other sites More sharing options...
JWW Posted November 14, 2009 Share #26 Posted November 14, 2009 Even though it was pretty much not noticeable, I wanted my M9 to be right on with my Noctilux and my 75 lux (more critical). Since I had done this with both my previous M8 and even my MP, I just spent 2 minutes with a (very) slight tweak of the 2mm allen adjust and it's right on to my specs. . It's such an easy adjust, it should be included in the instruction manual to avoid the returns. It reminds me of tweaking a carburetor idle adjust. Link to post Share on other sites More sharing options...
Guest mc_k Posted November 14, 2009 Share #27 Posted November 14, 2009 Advertisement (gone after registration) you should probably test a camera or lens after you notice a problem in your work, not before. From reading the focus test threads the last two years, I think the forum itself induces as many focus issues as actual out-of-spec equipment. The rangefinder test is not accurate to 1mm; should be obvious after you've done it a few times. The distance scale on a lens is a rough and ready guide, it is not there to measure millimeters either. Theoretically, even if you have two bodies and two lenses, you cannot know the absolute error of any of them; you have to compare to the standard. But practically, if you have a whole bunch of cameras and lenses, then sure, you have a good idea of what you should send back to be checked. Link to post Share on other sites More sharing options...
Guest mc_k Posted November 14, 2009 Share #28 Posted November 14, 2009 ...2mm allen adjust... ...has backfired on some Link to post Share on other sites More sharing options...
Guest mc_k Posted November 14, 2009 Share #29 Posted November 14, 2009 also it goes against experience that 12 lenses agree exactly. There should be some variation. Link to post Share on other sites More sharing options...
mwilliamsphotography Posted November 14, 2009 Share #30 Posted November 14, 2009 I have one of the first 20 M9s into the US. No issues with focusing as proven by pin-point focus of a 50/0.95 wide open at various distances. Back when I got my M8, all but one of my M lenses would not focus correctly as tested on a friend's M8 that was perfectly adjusted. It wasn't my M8, it was the lenses. After months of back-and-forth to Leica I can now say thumbs up for my a 50/1.4 ASPH.(recently sold), 90/2.8, 35/1.4 ASPH and 28/2 ... all of which are now on the money. Recently I've gone through 3 different 75/2 ASPHs looking for one that is in calibration. 2 back focused, and the latest one straight from Leica front focused by an indisputable margin. I would NOT shoot a job with anything from Leica until I totally tested in on a tripod, and in real world conditions. I think the change from film to digital has increased the need for vigilance on the part of the buyer even more than before. Marc Link to post Share on other sites More sharing options...
Alnitak Posted November 14, 2009 Author Share #31 Posted November 14, 2009 also it goes against experience that 12 lenses agree exactly. There should be some variation. Sure, there's variation, but they all front-focus. Sheesh. I'm not sure why you seem to be on mission to try and discredit my problem. It's folks like you that give a bad name to Leica owners by always blaming the user and not assigning any responsibility to Leica. It's pretty clear that a lot of people responding to this thread have had the exact same problem; let's just accept that there could have been a problem in production leading to some misaligned rangefinders going out. Link to post Share on other sites More sharing options...
Alnitak Posted November 14, 2009 Author Share #32 Posted November 14, 2009 you should probably test a camera or lens after you notice a problem in your work, not before. From reading the focus test threads the last two years, I think the forum itself induces as many focus issues as actual out-of-spec equipment. The rangefinder test is not accurate to 1mm; should be obvious after you've done it a few times. The distance scale on a lens is a rough and ready guide, it is not there to measure millimeters either. Theoretically, even if you have two bodies and two lenses, you cannot know the absolute error of any of them; you have to compare to the standard. But practically, if you have a whole bunch of cameras and lenses, then sure, you have a good idea of what you should send back to be checked. Let's be clear. When I said "initial testing" I meant just taking some typical pictures with the camera. In doing this, I noticed that every shot was slightly OOF. It was only after those results that I started to do some testing. As I indicated, the testing has shown that the camera front-focuses about 1/2 inch. This is with every lens I have. Every single one of those lenses focuses perfectly fine with my M8.2. Standard or no standard, I think that is a pretty definitive demonstration of the fact that the M9 rangefinder is off. BTW, the M9's rangefinder also won't ever focus on infinity. It's clearly out of alignment. Link to post Share on other sites More sharing options...
Guest mc_k Posted November 14, 2009 Share #33 Posted November 14, 2009 If you can't get coincidence at infinity (for example star or moon), or the image at infinity is unsharp, then something does need to go in for service. Link to post Share on other sites More sharing options...
arnold kaufman Posted November 14, 2009 Share #34 Posted November 14, 2009 Arnold, Think of this way. Let's say I used the 75 'cron, and set the lens at 0.7m. I then set a target at exactly 0.7m from the focal plane of the camera. If everything is calibrated correctly, the rangefinder patch will show the target perfectly focused, and the image will be in perfect focus. If the rangefinder is front-focusing, it will show the target as being out of focus, even the image will be in perfect focus. If I moved the camera back away from the target, a front-focusing rangefinder (or rather, one that is calibrated to the wrong distance relative to the true focal point) will show now show the image as being in focus in the rangefinder patch, but the real focal point of the image would be in front of the target, and the image will show that by being out of focus. Another way to think of it is if the target is at 0.7m, and the lens is set at 0.7m, and the image is in perfect focus, then the front-focusing rangefinder will think that the target is really at 0.71m. Now, this can be caused by the lens being out of calibration as well. One way to tell if its the lens or the camera is to try it with different lenses. If they all show a consistent misfocus in the same direction, then its the rangefinder. If just one lens shows a problem, then its the lens that is out of calibration. The f-stop matters because of course it affects the DOF. The DOF for the 75mm 'cron on an M9 at 0.7mm is only 9mm. If the rangefinder is calibrated to have the focus point exactly precise (and Leica claims millimeter-precise alignment), then I have just a few mm in front of and behind the target that will be in focus. That's why being off my 12-13mm, which is my case, is a big problem. That means that the entire target is out of the DOF zone, and is totally blurry. Or, the eyes are out of focus, but the tip of the nose looks great. Jeff Jeff Jeff Thank you for your response to my question I now know what everyone is talking about I intend to do some real testing on my 24mm Lux, 50mm Noctilux & 75mm Cron hopefully my cameras are focusing properly. Thank you again for your help. Arnold Link to post Share on other sites More sharing options...
ho_co Posted November 15, 2009 Share #35 Posted November 15, 2009 ... I just spent 2 minutes with a (very) slight tweak of the 2mm allen adjust and it's right on to my specs. ... Just remember that Leica tests and adjusts the rangefinder for three different distances (see the photos of the M9 production line Luigi mentioned) and previously did the same without electronic assistance. Leica specifically recommends against this home remedy, since adjusting for one distance (with the cam-tracker and Allen wrench) can throw the camera out for other distances. OTOH, as mentioned here, many folks on the forum have done well with the Allen key adjustment. Link to post Share on other sites More sharing options...
ho_co Posted November 15, 2009 Share #36 Posted November 15, 2009 ... Earlier this week I purchased a 75 cron & have had great sucess ... ... I intend to do some real testing on my 24mm Lux, 50mm Noctilux & 75mm Cron ... Arnold-- It's nice to be reassured, but if you're "having great success," you probably don't need to doublecheck. A good source is the chart offered at Nikon D70 Focus Chart. Just remember to do what's natural with the M, and shoot in portrait mode to make it easy to see the focus line. Link to post Share on other sites More sharing options...
arnold kaufman Posted November 16, 2009 Share #37 Posted November 16, 2009 Arnold--It's nice to be reassured, but if you're "having great success," you probably don't need to doublecheck. A good source is the chart offered at Nikon D70 Focus Chart. Just remember to do what's natural with the M, and shoot in portrait mode to make it easy to see the focus line. Howard, Thank you for kind words re: not not needing to double check close focusing.I really dont' shoot many portraits so my success is mostly with images out of the close up range. However I did test my 75mm Cron & it seems to be accurate using the method outlined by Jeff. I am wondering what you mean about shooting in the portrait mode, can you explain. Thanks, Arnold Link to post Share on other sites More sharing options...
jaapv Posted November 16, 2009 Share #38 Posted November 16, 2009 I think he means vertically. Link to post Share on other sites More sharing options...
arnold kaufman Posted November 17, 2009 Share #39 Posted November 17, 2009 I think he means vertically. Thank you I can do that,cheers. Arnold Link to post Share on other sites More sharing options...
ho_co Posted November 17, 2009 Share #40 Posted November 17, 2009 I am wondering what you mean about shooting in the portrait mode, can you explain. I think he means vertically. Yes, Jaap is right. To me, it's "vertical" and "horizontal," but I tried keeping up with the whippersnappers and got caught. (Glad to learn there's someone else who thinks the way I do. ) I even heard a museum docent comment a couple weeks back that a painting was "in portrait orientation." I'm afraid the anonymous They have won on this one. Glad your focus checks out, Arnold. It usually does, but it's reassuring to check. Link to post Share on other sites More sharing options...
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