algrove Posted June 15, 2012 Share #21 Posted June 15, 2012 Advertisement (gone after registration) on average for Leica Solms for something like a 75 Summilux? are we talking more than 2 weeks? My 75/1.4 took about 4 weeks at Leica NJ, but this was when most send in their lenses for such work (got it 6 bit coded too) February/March. Got it back early April. Link to post Share on other sites More sharing options...
Advertisement Posted June 15, 2012 Posted June 15, 2012 Hi algrove, Take a look here Lens calibration. I'm sure you'll find what you were looking for!
rramesh Posted June 15, 2012 Share #22 Posted June 15, 2012 Some people are under the false impression that Leica calibrates your lenses to "match" your specific body, which is absolutely false. Leica calibrates rangefinders and lenses to a standard, so that lenses and bodies are completely interchangeable with all the other bodies and lenses in the world. To do otherwise would be chaos, and would mean a return to the long retired practice of having bodies and lenses with matching serial numbers that could only be used together. My apologies if your OP was just a suggestion to have your favorite equipment regularly checked, but I agree that "if it ain't broke then don't fix it..." Correct me if I am wrong, but I believe older M lenses are by default calibrated for film and the newer ones by default to the closer tolerances of digital. Some, but not all of the older lenses can be re-calibrated by Leica for digital. This was what done when I sent in my 90 Elmarit-M. Link to post Share on other sites More sharing options...
StephenPatterson Posted June 15, 2012 Share #23 Posted June 15, 2012 Correct me if I am wrong, but I believe older M lenses are by default calibrated for film and the newer ones by default to the closer tolerances of digital. Some, but not all of the older lenses can be re-calibrated by Leica for digital. This was what done when I sent in my 90 Elmarit-M. Ramesh, it's important to remember that not all film is equal. With color film you are exposing through multiple emulsion layers and filter layers, whereas with B&W film only a single emulsion layer is exposed. For 35mm color film it might be anywhere from 15-25 microns thick whereas B&W can be less than 10 microns thick (on data sheets you will usually see this expressed as 10μm). For reference a human hair is about 100μm thick. Leica obviously never made "B&W Film Only" lenses, or "Color Film Only" lenses, so an average was chosen. And we haven't even discussed the fact that the camera film transport system and pressure plate must balance between stretching and pressing the film flat while not causing damage. My point is that when lenses were calibrated for film a certain tolerance was required to optimize the focal plane for somewhere in the middle of the emulsion layers, but in actuality the inherent tolerances of the system (opto-mechanical rangefinder, lens barrel cams, lens element variations in size and position) will preclude the sort of accuracy that I believe you are imagining. For exposing to a digital sensor we are of course trying to aim for the focal plane of the device, so in practical terms the tolerances as opposed to film are greatly reduced, but the tolerance limits of the rangefinder focus system remain. I have no data on the differences in the focal plane of the M9's digital sensor in relation to the "desired" focal plane within the emulsion layers of a 35mm film frame, but such a drawing would be interesting to study. Ramesh, I believe that your 90 Elmarit-M was simply calibrated to the latest spec and tighter tolerances which exist today. Link to post Share on other sites More sharing options...
espresso Posted June 15, 2012 Share #24 Posted June 15, 2012 there´s also a psychological effect when switching from film-m to digital-m. on film i hardly ever used the f 1.4 of the lux. this lens was semi asleep until i had i had it on the m9, when suddenly it became the most important lens of all, due to shallow dof and wonderful unsharp rendering. it was with the m9 when i noticed back focus issues of the lens first. on film many shots were unsharp, some were sharp, and i always attributed this to my abilities or missing abilities, never to the misalignment of the lens. only with the instant visibility of the digital results it became clear that it was the lens, not me. Link to post Share on other sites More sharing options...
maddoc2003jp Posted June 19, 2012 Share #25 Posted June 19, 2012 Some people are under the false impression that Leica calibrates your lenses to "match" your specific body, which is absolutely false. If so why would Leica ask me to send in my mainly used (film) body after having sent in my Noctilux 50/1.0 for calibration ? They insisted on this to specifically calibrate my main user camera body to that lens. Link to post Share on other sites More sharing options...
jaapv Posted June 19, 2012 Share #26 Posted June 19, 2012 Perhaps because Leica found, by checking the lens, that the camera was at least partly the cause? Link to post Share on other sites More sharing options...
maddoc2003jp Posted June 19, 2012 Share #27 Posted June 19, 2012 Advertisement (gone after registration) The Noctilux had been in for fixing a loose element in the front-group and for re-calibration of the lens they asked me to send in the - recently - proper overhauled and calibrated camera body. If they would calibrate lenses to a general standard, it would not make sense asking me to send in a calibrated camera body except for cross-checking. Link to post Share on other sites More sharing options...
jaapv Posted June 19, 2012 Share #28 Posted June 19, 2012 Well, I suppose, tolerances being what they are on these older lenses and bodies, that some tolerance-matching would not come amiss. Especially with a Noctilux, However, the resulting adjustment will still be to the fixed standard. Link to post Share on other sites More sharing options...
maddoc2003jp Posted June 19, 2012 Share #29 Posted June 19, 2012 Well, I suppose, tolerances being what they are on these older lenses and bodies, that some tolerance-matching would not come amiss. Especially with a Noctilux, However, the resulting adjustment will still be to the fixed standard. That makes some sense to me. Link to post Share on other sites More sharing options...
StephenPatterson Posted June 20, 2012 Share #30 Posted June 20, 2012 Sorry I've been traveling for a few days and did not get the chance to respond to maddoc2003jp's question, but I see Jaap has once again come to my rescue. Tolerance matching is exactly why Solms would want to check your film body M, especially if it was being used with a Noctilux. If the lens was on one end of the tolerance spec and the Noctilux were on the other then you might still not be happy with the result, so best to check both and if need be make additional adjustments within the tolerance band for one or both. Link to post Share on other sites More sharing options...
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