smeies Posted March 9, 2011 Share #1 Posted March 9, 2011 Advertisement (gone after registration) hi, i bought new lenses and used ones. with used ones i was able to focus from the first moment , nearly but with my new ones i think i have a focus shift, that disapears over time (few days) is it me or is this an effect known? cheers sascha Link to post Share on other sites More sharing options...
Advertisement Posted March 9, 2011 Posted March 9, 2011 Hi smeies, Take a look here focus on a new lens. I'm sure you'll find what you were looking for!
jaapv Posted March 9, 2011 Share #2 Posted March 9, 2011 :confused: Link to post Share on other sites More sharing options...
Lightwrangler Posted March 9, 2011 Share #3 Posted March 9, 2011 This forum attracts more and more funny guys. But i had a nice laugh anyway Link to post Share on other sites More sharing options...
smeies Posted March 9, 2011 Author Share #4 Posted March 9, 2011 good that i am usefull for some laughs hehe so i take it as a - you r nuts wait, my head is full of that Link to post Share on other sites More sharing options...
Lightwrangler Posted March 9, 2011 Share #5 Posted March 9, 2011 Yes, thanks for the laugh. But nevertheless I can't help you, because I don't understand your problem. Looks like you are mixing up a lot of terms. Read around the forum a bit and then come back with a more specific question. And then start by telling us what equipment you are using. Mike Link to post Share on other sites More sharing options...
smeies Posted March 9, 2011 Author Share #6 Posted March 9, 2011 ok i use a m9 and bought a new 2,5 90mm never got the focus right, was always behind my target after testing other lenses, i was sure it was not me, as all was fine a few days and lens changes later, the focus is now spot on (with the 90) i thought it was me in the beginning but i received now my 21, and the effect repeated so i was seriously wondering if it is me getting used to the lenses, or something else as i could not recal this effect at all with my previously bought used lenses that was all ... Link to post Share on other sites More sharing options...
jaapv Posted March 9, 2011 Share #7 Posted March 9, 2011 Advertisement (gone after registration) The lenses are partly from cast metal. After being cast the parts suffer from delayed shrink causing this effect....errmmm.. I think.... Link to post Share on other sites More sharing options...
Nicoleica Posted March 9, 2011 Share #8 Posted March 9, 2011 Could it possibly be that your new lenses are rather tight, and that you aren't locking them fully in place until you've changed them a few times and become used to handling them? (Yes, I know that this is clutching at straws, but I can't think of anything else at this time.) Link to post Share on other sites More sharing options...
mmradman Posted March 9, 2011 Share #9 Posted March 9, 2011 It is called learning curve, applicable to anything not only Leica. Link to post Share on other sites More sharing options...
Michael Geschlecht Posted March 9, 2011 Share #10 Posted March 9, 2011 Hello sascha, Welcome to the Forum. By focus shift do you mean the older lenses handle & focus accurately but the newer ones need to be excercised for a while before they respond appropriately to your focussing? If that is the case please keep in mind focus w/ a rangefinder camera is focus by proxy. W/ a SLR or digital screen you are looking @ whatever the lens is. There is no lack of connectivity or lag between the optical focussing of the lens & the mechanical alignment of it w/ the sensor/film or viewfinder. W/ a rangefinder camera a differentially machined helicoid in the lens is actuating a roller in the body connected to a mechanism which actuates a mechanism which moves a visual indicator perceived by the viewer as focussing. There is no optical continuity between what the lens sees & records on the sensor/film & the image viewed in the combined range/viewfinder. There is only a complex of mechanical linkages actuating mechanisms creating apparent visual focus. Sometimes these mechanisms whether in the lens, camera or both need to be excercised because of significant idle periods. For example: A new lens might sit on a shelf for years without use before its box is ever opened. It is often good to excercise all aspects of whatever a camera, lens or other piece of equipment can do to get their lubricants redistributed & for mechanisms to operate optimally. This is often more productive w/ less time & effort than sending something for service. These cameras & lenses are like Samoyeds: They are designed to work & be used on a regular basis & part of their design is to relubricate & optimize themselves thru use. Like a Samoyed they may enjoy an occasional afternoon on a couch but they are built to work & are @ their best when working. It is generally beneficial w/ many instruments designed to be used on a regular basis to excercise all aspects of everything they can do even if all aspects are not always called upon to be used. This also helps make you more proficient in their use. If this is the problem & you do excercise the system or the specific component accordingly in the majority of instances the problem will go away & the handling will improve. M's & their lenses are pretty much trouble free systems which can often operate for many years with very little attention if they are used on a reular basis. Best Regards, Michael Link to post Share on other sites More sharing options...
elgenper Posted March 10, 2011 Share #11 Posted March 10, 2011 hi,i bought new lenses and used ones. with used ones i was able to focus from the first moment , nearly but with my new ones i think i have a focus shift, that disapears over time (few days) is it me or is this an effect known? cheers sascha Well, such things happen in a more or less random way... FWIW, these are my experiences: Just over 13 months ago, my M9 was finally delivered. At that time I owned 3 old M lenses (35/2, 50/2 and 90/2.8, the classic combo), all made in the ´60es, and well used (I have an old M2 that I used them with). And, lo and behold: all 3 focussed perfectly with my new M9! Only, that old 35 was rather ´dreamy´ wide open, so I bought a brand new Sum 35 Asph - and it front focussed right out of the box! Back to Solms - twice. Now it´s on the spot, too. Wile waiting, I bought a 75 Summicron Apo, slightly used. And, it did focus perfectly, too. Recently, I bought a used 135 TeleElmar - back focussing terribly! So, I´d say, even old, beat-up lenses can be on the spot, or far off. Random occurrences, I´d say. What´s worse is that brand new lenses can be off right out of the box - and that should NOT happen, not with products from Leica! BUT - don´t mix this up with ease of focussing! Both my new Summicrons are FAR easier to find focus quickly with than any of my oldies. Obviously, it has nothing to do with the rangefinder itself, since that is the same for all lenses. What matters is the steepness of the focussing helicoids; the new ones are far steeper, so much less turning is required. Link to post Share on other sites More sharing options...
01af Posted March 10, 2011 Share #12 Posted March 10, 2011 In the context of optics and photography, the term focus shift is a technical term with a very specific meaning. If you're using it with a different meaning or in a colloquial way then you'll get less-than-useful answers. Link to post Share on other sites More sharing options...
bill Posted March 10, 2011 Share #13 Posted March 10, 2011 Simple things first... Are you looking straight through the viewfinder? Regards, Bill Link to post Share on other sites More sharing options...
Xmas Posted March 10, 2011 Share #14 Posted March 10, 2011 Could it possibly be that your new lenses are rather tight, and that you aren't locking them fully in place until you've changed them a few times and become used to handling them? (Yes, I know that this is clutching at straws, but I can't think of anything else at this time.) Some of the new lenses are stiff after a long flight from Solms, I prefer them that way but some people grumble and send them back. Nicol may be correct, it may be the lens loosening up. You seem to have activated all the trolls as well, tusk tusk... Noel Link to post Share on other sites More sharing options...
bill Posted March 10, 2011 Share #15 Posted March 10, 2011 You seem to have activated all the trolls as well, tusk tusk... I don't see anyone trolling here?? Regards, Bill Link to post Share on other sites More sharing options...
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