alainD Posted June 6, 2011 Share #1 Â Posted June 6, 2011 Advertisement (gone after registration) I recently bought on ebay an Elmarit 90mm (latest generation, 6 bit coded). I had it CLAed and focus adjusted. When it came back the first time, the focusing was still off by about 2-3 inches at short distance (front focusing), so I sent it back and now the focusing is off by only 1/2 inch to an inch at 3 feet. My testing procedure is simple: I take a portrait of my wife, focus on her eyes and I see her lens frames in perfect focus, not her eyes... I I change the focus a bit, moving it out a tiny bit, now the eyes are in focus. Â I use a 1.25 magnifying eyepiece, and I can focus perfectly with my Noctilux, even at f/0.95, at any distance... Same with my Summarit 75mm... (although I had to have it calibrated) Â I tested the Elmarit at longer distance (like 20 feet) and it is perfectly accurate there. I do not see this behavior on any of my other lenses... Â I'd like feedback form people who have this lens (on a M9) on what could cause this: - Is it my copy of this Elmarit that may have a problem? - It is a problem on the calibration job and I should send it back a second time? - Is it a typical problem on that model, where focus calibration can either be optimized for short distance or long distance, but not for both? - or it it me having too high expectation for a 90mm? Â - Alain. Link to post Share on other sites More sharing options...
Advertisement Posted June 6, 2011 Posted June 6, 2011 Hi alainD, Take a look here Focusing calibration of Elmarit 90mm. I'm sure you'll find what you were looking for!
Printmaker Posted June 6, 2011 Share #2 Â Posted June 6, 2011 Mine does the same. I either use F4 or 5.6 or back focus an inch. Once past 5 feet, the lens is fine. I've been meaning to send it in for calibration but am so accustomed to focusing on hair rather than eyes that I never got around to it. Link to post Share on other sites More sharing options...
wda Posted June 6, 2011 Share #3 Â Posted June 6, 2011 Alain, Welcome to the Forum! I also bought a mint condition version of this lens earlier this year and was immediately impressed by the accuracy of its focusing throughout the range. I believe mine had been back to Solms for 6-bit coding, which probably accounted for the premium price I paid. Focusing would have been checked at the time the new coded flange was fitted. Â It is a very fine lens and should give you excellent results. Why not try a different test subject, something static and use a tripod? Although I generally use a 1.4x eyepiece magnifier, sometimes when in a hurry I don't. On those occasions I do find I have to take more care in focusing. Depth of field at closest distance is very shallow at wide apertures. There is not much room for error, human or technical. Link to post Share on other sites More sharing options...
alainD Posted June 6, 2011 Author Share #4  Posted June 6, 2011 Alain, Welcome to the Forum!. Thank you!  It is a very fine lens and should give you excellent results. Why not try a different test subject, something static and use a tripod? Although I generally use a 1.4x eyepiece magnifier, sometimes when in a hurry I don't. On those occasions I do find I have to take more care in focusing. Depth of field at closest distance is very shallow at wide apertures. There is not much room for error, human or technical.  I tried on different subjects, same results. I'm used to narrow DoF with the Noctilux, so I've trained my exes to really pay attention to focusing... The results I'm getting are repeatable. See picture xxx36, focused on the eyes, picture xxx37 focused to tad further by rotating the focus ring by 1mm to the left.  I've found this review: Floating Elements Are Required Might be that it is really difficult to calibrate for both close and long distance...  Alain. 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/153606-focusing-calibration-of-elmarit-90mm/?do=findComment&comment=1694244'>More sharing options...
Michael Geschlecht Posted June 7, 2011 Share #5 Â Posted June 7, 2011 Hello Everybody, Â Welcome to the Forum alainD Â One way to test focus is to take a long ruler & place it on the ground in front of you pointing away from you. Now put your camera on a solid tripod w/ a solid head. As w/ all tripods: When it is possible 1 leg should be pointing in the direction of the center of your subject. Focus. Always focus on the middle #. Using the middle # means you never have to remember any #'s. Let the camera settle down for a minute or so & then gently release the shutter. Do this a number of times from both focussing directions. Look @ the results under hi magnification. The gradations of the rule will not only tell you if but also how much & from which direction focus was correct or incorrect. Â Focussing from both directions is important because sometimes a lens focuses correctly going in 1 direction & not in the other. Or sometimes it's a mix of results dependent on direction & distance. Â Do this repeatedly @ various distances you think your lens may be off. For example 3 & 5 meters both. Â Best Regards, Â Michael . Link to post Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.