johnloumiles Posted February 24, 2012 Share #1  Posted February 24, 2012 Advertisement (gone after registration) Hey I wanted to get some quick feedback before I rip this seller a new one. I purchased a Canon 50mm 1.2 FTM online and it cam in the mail today. I popped it on my M8 to test it out and to my surprise the focus is off by a foot or more.  The seller said in his listing that he tested the focus on a Leica IIIg and that it was spot on. How could it be so off when I received it other then he lied and only put it on the camera for show but never really got a shot developed?  It was packed properly and everything else seems to be in order. If I'm doing something wrong please tell me, I'd love to be the horses ass on this one. I have a feeling I am one regardless of who's fault it is.  Here are some test shots.  1st one is taken with a 50mm Elmar 2.8 (modern version)  2nd with the Canon.  Both were shot at 2.8 and the green horse head was used as focus spot.  Thanks for your help. 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/173488-new-vintage-lens-the-focus-off-by-a-foot-ideas/?do=findComment&comment=1936689'>More sharing options...
Advertisement Posted February 24, 2012 Posted February 24, 2012 Hi johnloumiles, Take a look here New * Vintage* Lens - The Focus Off by a Foot. Ideas?. I'm sure you'll find what you were looking for!
algrove Posted February 25, 2012 Share #2 Â Posted February 25, 2012 We all get screwed by buying used and I for one have had it and will not do it unless I can test it myself on my own camera before one cent is exchanged. Buy in your own backyard. You are asking about non leica gear so very few here will be able to help other than tell you to send it back. Link to post Share on other sites More sharing options...
pop Posted February 25, 2012 Share #3 Â Posted February 25, 2012 My elderly 35mm Summilux wasn't usable on the M8. It turned out that this was one of the very few Leica M lenses which had issues with the rangefinder coupling. It's even mentioned in an M8 FAQ by Leica, but it had not occurred to me to read that before buying the Summilux (second hand). Â Have you any means of testing your new lens on another type of body, such as an M4 or an LTM one? Link to post Share on other sites More sharing options...
Ecar Posted February 25, 2012 Share #4 Â Posted February 25, 2012 Which LTM to M adapter are you using? That may be the culprit, although the focus shift appears to be a fairly massive one. Link to post Share on other sites More sharing options...
johnloumiles Posted February 25, 2012 Author Share #5  Posted February 25, 2012 Thank you Pop & Ecar for your input regarding my issue. So to go in a little more detail:  Pop, I have heard about that incapability as well but I made sure to read up on the lens before I bought it and I found many photographers using it with their M8 (one example below)  http://www.stephenlee.info/p954598406  I ran a few test shots through my M6 so once I turn those in I'll get the whole picture. I was also about to try it on my R-D1 but the shutter faulted out of nowhere (and it was serviced 6 months ago, but that's a whole other headache).  Ecar, I also maybe thought that could be it as I'm using a 28/90 adapter (still waiting for the 50/75 to come in the mail) but I also have a Canon 50mm 1.5 LTM (sonnar type) and that works just fine with the adapter in question. Maybe it's a combination of the lens and the adapter since the two canon lenses are completely different designs. Again I'll know more once I get film back or the adapter. Like you said though it's a huge shift; exactly one foot after measuring.  The seller seems knowledgable but he has been beating around the bush. He talks about testing the lens on a ground glass, an M3 and so on but never actually saying he ran film through it even though I asked a few times. I don't know how the lens could get that far out of whack even if it had been used daily for 50 years.  I'll keep trying different variables and update you as to what happens. If anything I said turns on a lightbulb please let me know.  Thanks Again  John Link to post Share on other sites More sharing options...
Sp12 Posted February 25, 2012 Share #6 Â Posted February 25, 2012 Look at that Pastel color palette on the Canon. Link to post Share on other sites More sharing options...
lars_bergquist Posted February 25, 2012 Share #7 Â Posted February 25, 2012 Advertisement (gone after registration) I would never buy a lens, or a camera, by mail except from a reputable house that has a good name to defend. I have one (1) such address, and that is Leicashop in Vienna. Yes, Austria. Â I have told this story before, but: Before there was a 18mm Super-Elmar I bought a Zeiss 18mm ZM Distagon for my M8 which needed a useable wide angle lens. Nice optic but focus was more than one meter off at 4 meters. I sent the lens back to Leicashop. They checked, and mailed me back to tell me that two other Distagons on their shelf were off too! So they sent the lens back to Oberkochen, and it returned, via Vienna, now a well travelled Distagon but spot on. I can only speculate on the correspondence between Oberkochen and Cosina. Â This worked out fine because we had two companies with a reputation to care about, Leicashop and Carl Zeiss (of course). I now have a M9 and I still have the Distagon. It's a fine lens and occasionally I want something really wide. Â LB Link to post Share on other sites More sharing options...
jaapv Posted February 25, 2012 Share #8 Â Posted February 25, 2012 Hy don't you do a deal with the seller on the cost of adjusting it? Link to post Share on other sites More sharing options...
FlashGordonPhotography Posted February 25, 2012 Share #9 Â Posted February 25, 2012 Wouldn't a spacer fix this? Â Gordon Link to post Share on other sites More sharing options...
TomB_tx Posted February 25, 2012 Share #10 Â Posted February 25, 2012 I picked up a Canon IVB with Serenar 50 1.8. The Serenar is off by at least a foot on my M9 and film Leicas, but is fine on the IVB. I figure they were serviced and adjusted to match each other, not the correct neutral standard. Perhaps that was once true of your lens. Link to post Share on other sites More sharing options...
lars_bergquist Posted February 26, 2012 Share #11  Posted February 26, 2012 Wouldn't a spacer fix this? Gordon  I suppose you mean a spacer/shim between the bayonet ring and the mount. The problem is that a shim does not only move the lens mount but also the rangefinder cam, by the same amount. You need to move the lens without moving the cam.  Also, when the lens has to be moved closer to the film/sensor plane, as is the case with backfocusing, you would have to use a negative shim. This would have to be made out of antimatter, which is very expensive.  LB Link to post Share on other sites More sharing options...
johnloumiles Posted February 26, 2012 Author Share #12  Posted February 26, 2012 So as Lars stated I think the lens is not close enough to the plane. My other Canon LTM that focuses fine on the M8 sits deeper the in the adapter then the 1.2. Now the question is how do you get it closer to the plane. There's so many people using these on their digital M, with most saying the Canon 1.2 works just fine so I'm still scratching my head on that one. I only bought this lens for 1.2 so if I can't get a sharp image at that aperture it's just a nice paper weight.  The first image is the Canon 1.2 the second is the 1.5 (which focuses correctly) 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/173488-new-vintage-lens-the-focus-off-by-a-foot-ideas/?do=findComment&comment=1937650'>More sharing options...
jaapv Posted February 26, 2012 Share #13 Â Posted February 26, 2012 Which means removing/ replacing the internal shims of the lens. Maybe it has been serviced and reassembled incorrectly. Link to post Share on other sites More sharing options...
johnloumiles Posted February 26, 2012 Author Share #14 Â Posted February 26, 2012 Jaapv-Defintely possible as some of the aperture blades have been what looks like replaced or resurfaced. Waiting on a spanner wrench to come in the mail and I'll take a look. The seller refunded me some of the money. Link to post Share on other sites More sharing options...
jamesk8752 Posted February 26, 2012 Share #15 Â Posted February 26, 2012 Jaapv-Defintely possible as some of the aperture blades have been what looks like replaced or resurfaced. Waiting on a spanner wrench to come in the mail and I'll take a look. The seller refunded me some of the money. Â Unless you have access to a collimator and other specialist tools I'd strongly recommend sending it to an expert for repair/adjustment. As you live on the West Coast, I'd recommend John Van Stelten at Focal Point, Inc. - he can do just about anything a lens needs. Â Maybe the seller would split the cost of this service. Â Regards, Jim Link to post Share on other sites More sharing options...
UliWer Posted February 26, 2012 Share #16 Â Posted February 26, 2012 With an 1:1.2 lens which was designed many years ago you should exspect a considerable focus shift. Your first example picture - taken at 1:2.8 - could show maximum focus shift even if a shift of a whole foot seems a lot. I am not sure where you focussed for the second example, the left picture seems to be sharper for the lens than the right one. Link to post Share on other sites More sharing options...
johnloumiles Posted February 27, 2012 Author Share #17 Â Posted February 27, 2012 James- thanks for the info. I contact John via and see what he says. Regardless my curiosity will get the best of me and I will have to open it up to at least clean it. I did so with my other Canon LTM and it was pretty rewarding. Â Interestingly enough there is a website where someone went into great detail about cleaning the Canon 1.2 complete with picture references. You can check it out below.. Â http://portretteur.nl/index.php?option=com_content&view=article&id=84:cleaning-a-canon-50mm-12-rangefinder-lens&catid=37:lenses&Itemid=58 Â Uli- Both images with the horse heads were shot at the same distance, at the same aperture and with the same focus point (green horse head). I would expect a focus shift of 1 to 2 inches as is normal with fast old lenses but as you can see it's 12 inches (confirmed upon measuring) which I find un-usable for my purposes. Also the focus shift changes length as you focus further away, compounding the problem. Link to post Share on other sites More sharing options...
doubice Posted February 27, 2012 Share #18 Â Posted February 27, 2012 I just realized that nobody asked and John did not mention - how is the focus accuracy at 10m, 20m and infinity (for the metrically challenged - 30', 60' and I guess infinity;)..)? This would be a very important piece of information in diagnosing what the issue may be...... Â If focusing correctly at long distances and not at close ones, than we could talk about focus shift. However - I have never seen a lens 'shift focus' by 12" at a distance of what appears to be 8' to 12'..... Â Best, Â Jan Link to post Share on other sites More sharing options...
johnloumiles Posted February 27, 2012 Author Share #19 Â Posted February 27, 2012 Doubice - I was just testing that out. The focus is off at all measurements although it's hard to test if it stays back-focused at exactly 1 foot without a collimator when talking about an object 25 feet away but its close. So I guess your right that calling this a focus shift is incorrect. Link to post Share on other sites More sharing options...
doubice Posted February 27, 2012 Share #20 Â Posted February 27, 2012 John, Â I would say that if your rangefinder images coincide with the lens physically set to infinity, you will need to add some shims inside the lens (as was mentioned earlier in the thread). From what I can see in your photos, with the lens focused at say 6' (using the rangefinder), objects at 7' are sharp. So - the optics have to be moved forward to be able to bring focus closer. Â Movement of the optics and the rangefinder cam is linear with a 50mm lens - the optics and the cam move in and out at the same rate. If the lens, when set to infinity, brings the rangefinder image in focus, all one has to find is the correct distance for the optics. This could be done by adding a shim of a correct thickness. With a digital Leica M this is somewhat easier to do than with a film M; where you definitely would need a collimator. With a digital M, the trial and error technique does not take as long.... Â I hope my ramblings make sense. Â Lars' suggestion of using a negative shim made of antimatter would be an excellent one, if one needed to bring the optical unit closer to film (or sensor) plane... Â Cheers, Â Jan Link to post Share on other sites More sharing options...
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