moreammo Posted September 19, 2012 Share #1 Â Posted September 19, 2012 Advertisement (gone after registration) i have a 50 Summicron with built in hood from 2003. the focus ring stops dead at infinity but going the other way it goes a tad bit past the closest focus marked. is this normal? focus is smooth and most photos seem in focus but some seem to be back focused just a tad. example: i took a head shot yesterday at about 6 feet away and focused on her teeth. At f5.6 the teeth were in focus but the nose was not. normally i get 1/3rd the DOF in front of where i focused (as i should) but this all seemed behind as the rest of her was is sharp focus. thoughts? Link to post Share on other sites More sharing options...
Advertisement Posted September 19, 2012 Posted September 19, 2012 Hi moreammo, Take a look here normal... need help maybe?. I'm sure you'll find what you were looking for!
parsod Posted September 19, 2012 Share #2  Posted September 19, 2012 I have the 50 summicron latest version and it also goes a little bit past the closest mark 0.7 so I think that is normal. It is the same thing for my 35 summicron and both of these lenses focus perfectly on my M9 even wide open. Could be your rangefinder and/or lens needs adjustment but I would do some more exact test with the camera on a tripod and still subjects. Maybe you or your model moved slightly in the example you mentioned. /Best regards - Paer  Link to post Share on other sites More sharing options...
lars_bergquist Posted September 19, 2012 Share #3 Â Posted September 19, 2012 Most M lenses do focus a bit closer than the marked minimum. The rangefinder does in fact work a bit closer than 0.7m. So this is perfectly all right. Â All lenses do in fact exhibit a bit of focus shift when stopping down because with spherical lenses, peripheral and axial light rays do not come to exactly the same focus. Fast lenses show more of this, simply because their lens elements have larger diameters, so there are more of the troublesome peripheral rays. With many modern superfast lenses, measures have been taken (one or two aspherical lens surfaces, floating elements) to keep this shift within negligible limits. Â The focus shift of the old 50mm Summicron should however remain completely within the depth of field, even when stringently applied. If you do have real problems with this lens, not caused by 'pilot error', then either the lens or the rangefinder may be out of whack and need adjustment. Any competent Leica technician should be able to do this. Â The old man from the Age of the Measuring Tape Link to post Share on other sites More sharing options...
pico Posted September 19, 2012 Share #4 Â Posted September 19, 2012 example: i took a head shot yesterday at about 6 feet away and focused on her teeth. At f5.6 the teeth were in focus but the nose was not. normally i get 1/3rd the DOF in front of where i focused (as i should) but this all seemed behind as the rest of her was is sharp focus. thoughts? Â That's strange. DOF total at 6' with that lens and f-stop is ~22 inches. The distance difference of her nose and teeth is very much shorter. One would hope. Link to post Share on other sites More sharing options...
moreammo Posted September 19, 2012 Author Share #5  Posted September 19, 2012 Thanks for the replies. it is very possible that in the cases where the focus was off, including yeterday, i am the one who moved or the model moved. as i recall i focused with the camera horizontal and shot vertical so maybe i shifted forward a few inches. the photo came out fine and the out of focus nose was only just so. in fact it lent itself to soften the left cheek as well as the nose, her face was turned to the right.  i will do some exact testing and see if there is an issue. good to know the focus ring is normal  how does one go about adjusting it if it is off? or adjusting the camera? Link to post Share on other sites More sharing options...
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