WarriorJazz Posted February 5, 2011 Share #1 Posted February 5, 2011 Advertisement (gone after registration) I just purchased a 90mm Summicron (E55) lens. Today I finally had some time to shoot some test images. After reviewing the test results I found out that all the shots came out blurry. After reviewing it more up close I saw that the focus is off and totally different items are sharp. It this the so called Front-focus/Back-focus problem? And is this a camera issue or is my newly acquired lens the problem? I never had focus problems with my 35mm f2 asph. In this picture I focussed on the text of the card. http://www.flickr.com/photos/warriorjazz/5417598289 Link to post Share on other sites More sharing options...
Advertisement Posted February 5, 2011 Posted February 5, 2011 Hi WarriorJazz, Take a look here Camera? Lens? Human?. I'm sure you'll find what you were looking for!
Nicoleica Posted February 5, 2011 Share #2 Posted February 5, 2011 Hi, sorry to hear about your problem. Looking at your example though, it could be any one of the 3 reasons that you suggested. The focus point does appear to be a little closer than your aim point. But at such a short range this could caused by the smallest of focussing errors or even movements of the camera after focussing. I think that to be able to determine any problem, you will need to perform a series of tests with the camera firmly mounted on a tripod. If you can perform these tests with another lens as well, this will further help in determining any problem. Good luck. Link to post Share on other sites More sharing options...
SJP Posted February 5, 2011 Share #3 Posted February 5, 2011 Does it make a difference if you focus starting from "infinite" or from "close focus"? If so there could be some slack in the lens (or rangefinder cam). Having said, accurate close focussing a 90 mm f/2 lens wide open is very difficult and takes some practice. I live in the Hague which is close to Roterdam, if you like you can try out my 1966 tele-elmarit 90/2.8 to compare. My camera is with dr. Leica in Solms so we can't compare our bodies..... () Please PM if interested, via this site or flickr (see below) Link to post Share on other sites More sharing options...
WarriorJazz Posted February 5, 2011 Author Share #4 Posted February 5, 2011 @Nicoleica: Thanks for your advice. I'll do some testing with a friends lens to be sure. @SJP: Thanks for the offer. I actually live in The Hague too. Just before your post I actually rang a friend to ask him to lend his tele-elmarit for a test. ;-) Personally I think the camera is off. I have used my friends tele-elmarit before and I found it difficult to focus and most of the shots were off. What are the chances of those two lenses being off,..right? I tried to focus on most apertures and they are all off. By now I guess I can take out the human factor as being part of the problem... Other question: Does this happen allot with leica camera's? Does these need to be calibrated on a regular basis? My M8 went to Solms about a year ago for a shutter fault problem and they said they calibrated it tthen. My m8 needs to go back anyway because of the famous "coffee-stain" problem on it's LCD. So they can re-check it then. Link to post Share on other sites More sharing options...
lct Posted February 5, 2011 Share #5 Posted February 5, 2011 I just purchased a 90mm Summicron (E55) lens. Today I finally had some time to shoot some test images. After reviewing the test results I found out that all the shots came out blurry. After reviewing it more up close I saw that the focus is off and totally different items are sharp. It this the so called Front-focus/Back-focus problem?And is this a camera issue or is my newly acquired lens the problem? I never had focus problems with my 35mm f2 asph... My pre-asph 90/2 does this as well but beware that the M8's rangefinder is not accurate enough to warrant high hit rates at f/2 due to the crop factor and the relatively low viewfinder's magnification. Should be fine at f/2.8-f/4 though so i would test the lens at those apertures before deciding which is the culprit. Link to post Share on other sites More sharing options...
WarriorJazz Posted February 5, 2011 Author Share #6 Posted February 5, 2011 My pre-asph 90/2 does this as well but beware that the M8's rangefinder is not accurate enough to warrant high hit rates at f/2 due to the crop factor and the relatively low viewfinder's magnification.Should be fine at f/2.8-f/4 though so i would test the lens at those apertures before deciding which is the culprit. Thanks for the tip. I didn't know that. I tried it but all apertures are the same. Link to post Share on other sites More sharing options...
lct Posted February 5, 2011 Share #7 Posted February 5, 2011 Advertisement (gone after registration) Does the lens rattle when you shake it? Mine does it hence my question. Link to post Share on other sites More sharing options...
SJP Posted February 5, 2011 Share #8 Posted February 5, 2011 Sounds like a rangefinder adjustment that Wil van Manen in Zoetermeer could do in a couple of days @ at modest price. Best to bring lens(es) and body. My experience with him was good & he was recomended to me by jaapv. Link to post Share on other sites More sharing options...
Shootist Posted February 5, 2011 Share #9 Posted February 5, 2011 Actually this sounds more like a lens problem. That is IF all your other lenses focus correctly. If this is a used lens then it may need adjustment for use on any digital M camera. But then it could also be user error. Since no M camera has a built in diopter adjustment do you see the rangefinder patch clearly? Are you wearing glasses? Or do you use a diopter correction lens on the eye piece? All this will cause the miss focusing of longer lenses. Especially wide open. Link to post Share on other sites More sharing options...
WarriorJazz Posted February 5, 2011 Author Share #10 Posted February 5, 2011 Actually this sounds more like a lens problem. That is IF all your other lenses focus correctly.If this is a used lens then it may need adjustment for use on any digital M camera. But then it could also be user error. Since no M camera has a built in diopter adjustment do you see the rangefinder patch clearly? Are you wearing glasses? Or do you use a diopter correction lens on the eye piece? All this will cause the miss focusing of longer lenses. Especially wide open. I only have a 35mm Summicron and that lens focusses perfectly and like i said in my prior posts, I have had some problems with a tele-elmarit but I thought then it was the lens. No, I don't have glasses or use a diopter. Link to post Share on other sites More sharing options...
WarriorJazz Posted February 5, 2011 Author Share #11 Posted February 5, 2011 Sounds like a rangefinder adjustment that Wil van Manen in Zoetermeer could do in a couple of days @ at modest price. Best to bring lens(es) and body. My experience with him was good & he was recomended to me by jaapv. Thanks for the tip! I might suggest the shopowner to let him adjust the lens for me .I still have a warranty on the lens but I want a specialist to handle it. Link to post Share on other sites More sharing options...
DOUG66 Posted February 5, 2011 Share #12 Posted February 5, 2011 Have a look at the thread "Focussing issues" in the Customer Forum which was started on 09/09/2010 in which I described a method of focussing an M rangefinder using a laser pointer. It improves the accuracy and removes the human eye factor when testing lenses. Doug. Link to post Share on other sites More sharing options...
WarriorJazz Posted February 5, 2011 Author Share #13 Posted February 5, 2011 My friend (the one with the Tele-elmarit) reminded me that I shot a few quick shots with his lens two months ago. I checked all my memory-cards and I found them! And you know what... it is sharp and focussed on the right spot! Check out the result: Focus Tele-elmarit | Flickr - Photo Sharing! As you can see I focussed on my sons eye and the crop shows that it's sharp. So I guess this is the evidence that the lens is the problem! Link to post Share on other sites More sharing options...
jamesk8752 Posted February 5, 2011 Share #14 Posted February 5, 2011 I'm not sure if you have just purchased the older 90 pre-AA or current 90 AA lens - I have the former and had a lot of difficulty getting sharp shots with it, even on a tripod. I sent it to DAG for adjustment and, he was able, after some difficulty, to improve the focusing accuracy. He advised that some 90s just don't seem to take to digital. Bottom line - I think that the advice to visit Mr. Van Manen with lens and body in hand is good, and that he will be able sort things out for you. Regards, Jim Link to post Share on other sites More sharing options...
epand56 Posted February 6, 2011 Share #15 Posted February 6, 2011 I'm with Stephen, a rangefinder adjustment is needed. I had the same problem in the beginning with my M8. Ok with short lenses but strong focus shift with long ones. It was my rangefinder vertically misalligned. After adjustment anything was ok. Link to post Share on other sites More sharing options...
WarriorJazz Posted February 7, 2011 Author Share #16 Posted February 7, 2011 I'm with Stephen, a rangefinder adjustment is needed. I had the same problem in the beginning with my M8. Ok with short lenses but strong focus shift with long ones. It was my rangefinder vertically misalligned. After adjustment anything was ok. But how come the shot taken with the Tele-elmarit is sharp? Why do you think its the rangefinder? Link to post Share on other sites More sharing options...
Shootist Posted February 7, 2011 Share #17 Posted February 7, 2011 But how come the shot taken with the Tele-elmarit is sharp? Why do you think its the rangefinder? Vertical alignment is a critical part of getting clear sharp images, IMHO. If the vertical alignment is off it is hard to tell when you really have correct focus on the subject/part of image you want to be in focus. One way to check vertical alignment is by focusing on lines intersecting at 90°. If you see 2 horizontal lines or just a wider horizontal then what is actually there then the vertical alignment is off. I don't believe your rangefinder is off. But if the vertical alignment is off, even the slightest, it will cause hit and miss focusing. Link to post Share on other sites More sharing options...
wstotler Posted February 7, 2011 Share #18 Posted February 7, 2011 It this the so called Front-focus/Back-focus problem? In this picture I focussed on the text of the card. Focusproblem | Flickr - Photo Sharing! Note that I see in the thread above that you tested the lens at all apertures--I'm posting this just to show a more rigorous method of testing. If you've already done this precisely, great! You're already to Case Two. . . . As lct said, the 90s are tough to focus proof-positive at a wide aperture. I focus mine with a magnifier. It *may* be a hardware issue, requiring your lens and/or M8 go on a holiday. But it *may* be a human error issue, too. This quick test works for all lenses and is designed to isolate error to the user (Case One) or to the hardware (Case Two). Performing this test on a tripod where you can *slightly* nudge the camera forward/back would be ideal. But you can hand-hold at 1/500th if you have enough light and coordination. Repeating the test multiple times increases sample size and certainty--provided you get a similar outcome with every test. Test Procedure: (1) Focus precisely on the target. Shoot. (2) Lean forward a *slight* bit. Shoot. (3) Lean forward a *slight* bit more. Shoot. (4) Focus precisely on the target by leaning backward to your original position. Shoot. (5) Lean backward a *slight* bit. Shoot. (6) Lean backward a *slight* bit more. Shoot. (7) Pull photos and examine them. Case One (user error): (A1) If you *could not* see a real difference in the rangefinder patch when "lean focusing" AND (B1) One of your shots (any shot) from the test is in sharp focus THEN (C1) Repeat the test with three different objects to confirm A1 and B1. (D1) If A1 and B1 are true, it is likely you are having an issue discerning the focus point precisely in the RF patch because you are within the "margin of error" for focusing the 90mm at a low aperture on your M8 with your eyeballs/technique. One shot from each set will always be "most" in focus--but the shot that is in focus is random (sometimes when you're leaning forward, sometimes when you're leaning backward). The rangefinder patch always looked "almost the same." Perhaps the "contrast" shifted a little--but you really didn't see any "ghosting" in the RF patch, indicating misfocus. This is human error. At least in the sense that you can't discern any difference in the RF patch--it always "looks" in focus--when it is not. Solutions: --> Suggest trying a 1.25x or 1.4x magnifier to enlarge the RF patch. Repeat the test. --> Suggest stopping the lens down (yes, I know, not ideal) to widen depth of field and eliminate focusing error from lack of being able to discern focus in the RF patch. Case Two (hardware error): (A2) If you *could* see a real difference in the rangefinder patch when "lean focusing" AND (B2) One of your shots from the test is in sharp focus THEN (C2) Repeat the test three times with other objects to confirm A2 and B2. (D2) Now, check your images to see if they are consistently in sharp focus when you are leaning slightly backward or leaning slightly forward. IF you discover that your images are consistently in sharp focus when leaning forward or are consistently in focus when leaning backward (one or the other)--but you saw discernible misalignment "ghosting" in the RF patch at the time of shooting that corresponds with the sharp, in focus image you took--you can likely say that you should investigate misalignment in RF. This is hardware error. The RF is mis-reporting where the plane of focus is falling--the plane of focus is actually falling in front of or behind the target. Solutions: --> Have the rangefinder calibrated. Repeat test. --> Have the lens examined/CLAed. Repeat test. Good luck! Will P.S. I *love* your thread title: Camera? Lens? Human? That is absolutely the question. Thanks much for posting and NOT immediately assuming it was your lens and rangefinder. Link to post Share on other sites More sharing options...
WarriorJazz Posted February 9, 2011 Author Share #19 Posted February 9, 2011 Note that I see in the thread above that you tested the lens at all apertures--I'm posting this just to ... Thanks wstotler for your reply. I have tried your method and I still think the lens is the problem. A friend of mine borrowed me his film leica and I'll have one final check before I send it back to the shop. Link to post Share on other sites More sharing options...
WarriorJazz Posted February 13, 2011 Author Share #20 Posted February 13, 2011 Today I decided to send the Summicron back. After testing it on another m8 and a m4-p it was getting clear it was the lens. Still I have a feeling my rangefinder is off. This would be very strange because it was adjusted last year. I'll have a clear answer next week when I'll have it checked by a technician. So this time it was not the human but The gear. Thanks everybody for al the advice! :-) Link to post Share on other sites More sharing options...
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