rob_w Posted September 28, 2009 Share #1 Posted September 28, 2009 Advertisement (gone after registration) I know there have been many threads on focus related issues. Normally my focus problems are entirely self-inflicted. However, I have a brand new 75 SA which I have been using for some months. I have been using it for portraits and focus seems to be spot on.but recently I have been using it for landscapes. On close scrutiny it seems not to be entirely sharp at infinity. Is this possible -- i.e. for a lens to be sharp at close and medium distance but not at infinity? Would appreciate your comments and whether I should have it checked. Maybe I should send my whole set in for CLA while I am currently in Europe? Who would I contact at Solms to arrange that? Many thanks Robert Link to post Share on other sites More sharing options...
Advertisement Posted September 28, 2009 Posted September 28, 2009 Hi rob_w, Take a look here 75 Summicron Asph - focus out at infinity?. I'm sure you'll find what you were looking for!
Shootist Posted September 28, 2009 Share #2 Posted September 28, 2009 For me to use the end, infinity, stop on the 75 Cron ASPH the subject has to be FAR FAR away. In this shot I was on the top of the Mt Mohonk tower looking down at the Mountain Lodge which is quite a ways away and I wasn't at the infinity stop of the 75 Cron. 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! Also the farther out you get the less detail everything in the image will have. Then you have to deal with atmospheric haze that you don't have at close up objects. The nect question is are you really focusing or just turning the lens to the infinity stop thinking the subject you are taking a image of is far enough away to use that stop? Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! Also the farther out you get the less detail everything in the image will have. Then you have to deal with atmospheric haze that you don't have at close up objects. The nect question is are you really focusing or just turning the lens to the infinity stop thinking the subject you are taking a image of is far enough away to use that stop? ' data-webShareUrl='https://www.l-camera-forum.com/topic/98346-75-summicron-asph-focus-out-at-infinity/?do=findComment&comment=1052834'>More sharing options...
rob_w Posted September 28, 2009 Author Share #3 Posted September 28, 2009 Very interesting feedback, thanks. I have noticed it recently on landscape photos of (relatively) distant buildings -- say 500 metres and beyond. I guess I turned to infinity presuming that distance was sufficient to require infinity focusing. If your experience is different I will test setting the focus more carefully. Can't say I have ever known a lens which still needs to be focused at that distance, however! Link to post Share on other sites More sharing options...
Nicoleica Posted September 28, 2009 Share #4 Posted September 28, 2009 Very interesting feedback, thanks. I have noticed it recently on landscape photos of (relatively) distant buildings -- say 500 metres and beyond. I guess I turned to infinity presuming that distance was sufficient to require infinity focusing. If your experience is different I will test setting the focus more carefully. Can't say I have ever known a lens which still needs to be focused at that distance, however! If I may add one small point. The infinity focus point is also affected by temperature, as lens/camera components may expand/contract a little. This is why many lenses will actually focus past the infinity mark on the barrel. Link to post Share on other sites More sharing options...
Seeingeye Posted October 2, 2009 Share #5 Posted October 2, 2009 Robert My own 75 Cron, bought secondhand, does much the same. By coincidence, I was experimenting with it this afternoon as I am considering having it serviced to see if this cures the problem. It seems to need a slight tweak back from infinity to be in focus, even at small apertures. I am wondering whether this is an issue similar to the one that M8 owners experience with the 35 Lux. So far, there do not seem to be any similar complaints about either lens on the M9 forum. Could it be something about the way the M8 and these lenses are set up as standard at the factory that creates a conflict, meaning an adjustment is necessary? As I have more or less decided that I will be getting a M9 in the near future, my next step is to try my 75 Cron on a demo model. There is not much point in calibrating the lens for the M8 if I have to get it redone soon after. Regards Mike Link to post Share on other sites More sharing options...
misha Posted October 2, 2009 Share #6 Posted October 2, 2009 I had the same problem two years ago with a brand new 75. i was told it focused 'beyond infinity'. It was successfully adjusted in NJ. cheers misha PHOTOGRAPHY BY MISHA FRIEDMAN Link to post Share on other sites More sharing options...
Stevez4 Posted October 3, 2009 Share #7 Posted October 3, 2009 Advertisement (gone after registration) Leica has requested both my m8 and the 75 Summicron to calibrate exactly. I lost part of a shoot of a once every ten years religious festival in Italy due to the infinity prob. Link to post Share on other sites More sharing options...
rob_w Posted October 3, 2009 Author Share #8 Posted October 3, 2009 Well, I am glad I asked the question here. After the feedback (thanks everyone) I tested very carefully. When set to infinity the lens is focused slightly beyond infinity. For subjects at, say, 500m to 1000m it is better to backoff just a slight amount. The result is perceptibly sharper. Who should I contact at Leica (Solms) to arrange for proper calibration? Never had to do this before. Thanks all, Robert Link to post Share on other sites More sharing options...
hoppyman Posted October 3, 2009 Share #9 Posted October 3, 2009 Here are some contact details, (for English speaking). Leica Camera AG Customer Service Solmser Gewerbepark 8 / D-35606 Solms / Germany www.leica-camera.com / andrea.frankl@leica-camera.com Telephone +49(0)6442-208-189 / Fax +49(0)6442-208-339 That lady is on holidays currently but this gentleman should be able to assist right now eberhard.jakob@leica-camera.com I suggest that you contact them first to determine where any actual error exists. It is also possible that this is a camera adjustment issue (or neither or both!). In any event Customer Service will advise you and your equipment would receive an initial assessment to determine what is required and you would then be sent an estimate. Link to post Share on other sites More sharing options...
rob_w Posted October 4, 2009 Author Share #10 Posted October 4, 2009 Thanks Geoff. BTW I like the tag line in your signature -- it often comes to mind when I am reading "those" posts where it is relevant (Maybe it should be sticky at the top of the forum) Cheers Robert Link to post Share on other sites More sharing options...
scsambrook Posted October 4, 2009 Share #11 Posted October 4, 2009 If I may add one small point. The infinity focus point is also affected by temperature, as lens/camera components may expand/contract a little. This is why many lenses will actually focus past the infinity mark on the barrel. This is by no means a "small point" and you really deserve a medal for bringing it up. The effects of temperatures on rangefinders were only too well known to armed forces back in the days when that's how distances were measured, and instruments calibrated in temperate climates (say circa 20 degC/68 degF) would often read inaccurately at levels of 30 degC or over. Rangefinders built on the stereoscopic principle (typically by Zeiss) were less affected than moving image patterns (some Zeiss, Barr & Stroud, Bausch & Lomb and others) where expansion of both optical and mechanical components created a variety of range reading errors. I have never seen reports of complaints about errors at low temperatures, but I think it would be quite possible for them to occur. Perhaps those of us encountering focus errors might consider whether temperatures might be playing a part. And perhaps Leica Camera might even be asked for an expert opinion. Link to post Share on other sites More sharing options...
Pedro Posted October 11, 2009 Share #12 Posted October 11, 2009 Please refer to the post on infinity focus at Diglloyd blog here diglloyd.com blog: October 2009 A bit scary while using a rangefinder (without live view). Link to post Share on other sites More sharing options...
carstenw Posted October 11, 2009 Share #13 Posted October 11, 2009 I have found that with several of my lenses, from 35-75 and 90, I need to focus on the subject, even if it is at several kilometres distance. Just snapping the lens to infinity results in a noticeably softer image. Before I tested this from the office tower in which I work, I would never have thought that it could make such a difference. Link to post Share on other sites More sharing options...
giordano Posted October 11, 2009 Share #14 Posted October 11, 2009 I have found that with several of my lenses, from 35-75 and 90, I need to focus on the subject, even if it is at several kilometres distance. Just snapping the lens to infinity results in a noticeably softer image. Before I tested this from the office tower in which I work, I would never have thought that it could make such a difference. This suggests that the system isn't correctly adjusted. Using a 90mm lens at f/2 with a minuscule 0.005mm circle of confusion (i.e. smaller than an M8 pixel), the hyperfocal distance is 1080m, so there's no possibility of distinguishing focus-wise between objects at or beyond that distance. Not that the Leica rangefinder is big enough to work at such a range anyway. Link to post Share on other sites More sharing options...
carstenw Posted October 11, 2009 Share #15 Posted October 11, 2009 This suggests that the system isn't correctly adjusted. Using a 90mm lens at f/2 with a minuscule 0.005mm circle of confusion (i.e. smaller than an M8 pixel), the hyperfocal distance is 1080m, so there's no possibility of distinguishing focus-wise between objects at or beyond that distance. Not that the Leica rangefinder is big enough to work at such a range anyway. Well, I have 5 rangefinder-coupled Leica lenses, and they all act the same, so either I have 5 lenses and 1 body out of whack, or there is another reason. Math aside (and my degree is in math), have you tried it? Link to post Share on other sites More sharing options...
giordano Posted October 12, 2009 Share #16 Posted October 12, 2009 Well, I have 5 rangefinder-coupled Leica lenses, and they all act the same, so either I have 5 lenses and 1 body out of whack, or there is another reason. The body out of whack would be enough. But we need to be quite clear about the symptoms. I understand that when photographing very distant objects you get the sharpest results when the lens's focusing ring (any of the five of them) is turned slightly closer than infinity. That's fine: it simply suggests that the lens flange is not quite far enough from the film (or sensor). But you say you "need to focus on the subject, even if it is at several kilometres distance." Does this mean that when the focusing ring is set at infinity, the rangefinder shows a double image of an object say 2km distant and that you turn the focusing ring to bring the image into alignment in the usual way? - or does your rangefinder actually give you different focus positions between an object 2km distant and one 10km distant? If the former, it again suggests that the body needs adjustment. If the latter, I boggle. Math aside (and my degree is in math), have you tried it? I seem to get sharp photos of distant objects when I set the lens to infinity - except for one lens which needed adjusting. Link to post Share on other sites More sharing options...
ho_co Posted October 13, 2009 Share #17 Posted October 13, 2009 Carsten-- I'd try a through-focus test. Sounds as if everything might be in tune but not necessarily properly aligned. FWIW--With my 75/1.4 I found that the infinity stop was just beyond infinity, even though the rangefinder and infinity stop matched. Images I shot focused by rangefinder at infinity weren't sharp. If I rotated the focus ring about one millimeter, the image became sharp. I then found that at any focus distance that I set by rangefinder, I would get a sharper image by rotating the focus ring just barely closer. I know that's not the problem you're describing, and except for the facts that a) you've noticed the discrepancy; and there shouldn't be a discrepancy; it might not be worth pursuing. Link to post Share on other sites More sharing options...
Seeingeye Posted October 13, 2009 Share #18 Posted October 13, 2009 I have just taken my lens to Ivor Cooper at Red Dot Cameras and he confirmed that my copy is front focussing. He has suggested sending both the camera and lens back to Leica for adjustment, which he is willing to arrange. Excellent service, considering that I did not buy either from him. Guess I now know where I will be placing my M9 order! Regards Mike Link to post Share on other sites More sharing options...
carstenw Posted October 13, 2009 Share #19 Posted October 13, 2009 I guess yours was focused further forward than mine. When I first got the camera, I figured that focusing on very distant objects (>100m back then, later >500m perhaps) was equivalent to just turning the lens to the end of the scale. However, I noticed a very slight softness when I did this, with lenses from 35-90mm. Then I did a rigorous test from my office, from where I can see half of Berlin (exaggeration, but I can see many kilometres), and it turns out that there is a very slight difference between, say, 2km and infinity, when focusing. This slight difference translates to a slight softness if you don't actually focus, but just snap the lens to infinity. Since then, I have always focused properly, no matter what the difference. It is a very small movement, but it makes a visible difference. Link to post Share on other sites More sharing options...
Seeingeye Posted October 13, 2009 Share #20 Posted October 13, 2009 I guess yours was focused further forward than mine. When I tested on my M8, it seemed to be OK at intermediate distances with focus at infinity being the issue. When Ivor put the lens on a M9 and tried it with this test chart http://focustestchart.com/focus21.pdf, it front focussed! So I am giving up trying to work out what is going on and will let him send both lens and body back to Leica. That way, if either is out of alignment then everything should get sorted at the same time. Before going back to Ivor, I'll also be checking my other lenses with the chart (which I have not previously seen) to see if they exhibit the same symptons. I think everything else is OK, but I'm getting a bit paranoid as a 35 Lux I tried had similar problems, although I do know this is a problem lens on the M8. There is also a similar ongoing thread on the forum about focus issues, which does not help my concerns, either. http://www.l-camera-forum.com/leica-forum/leica-m8-forum/101811-wacky-focus-issue.html Regards Mike Link to post Share on other sites More sharing options...
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