Keith (M) Posted February 15, 2011 Share #1 Posted February 15, 2011 Advertisement (gone after registration) My new M7 arrived this morning, much to my delight. However, I was astonished at the ease with which the lens bayonet engaged and locked. On my three-month old M9, turning a lens towards the lock position takes a very firm grip indeed and once the 'click' has occurred, there is absolutely no play whatsoever, rotationally or longitudinally. With the M7, the rotation is very easy (almost knife through butter) and once locked in place, it is possible to rock the lens very slightly either side of the lock position (no longitudinal play/movement discernible). I have spoken with the dealer, who in turn has spoken with Leica Milton Keynes and have been informed that this is normal (and that M9 might actually "be a bit on the tight-side"). I should add that my lenses are all less than three months old. So my urgent question to M7 owners - do your camera/lens combination's also allow a very slight rotational rocking movement of the locked lens? Link to post Share on other sites More sharing options...
Advertisement Posted February 15, 2011 Posted February 15, 2011 Hi Keith (M), Take a look here New M7 - Movement in mounted lens. I'm sure you'll find what you were looking for!
andybarton Posted February 15, 2011 Share #2 Posted February 15, 2011 I will check for you at lunchtime, but there were reports here recently of some M9 mounts being very tight indeed. FWIW, from memory, my M2 mount and my M7 mount are pretty much identical, even though there is 43 years between them. Link to post Share on other sites More sharing options...
Xmas Posted February 15, 2011 Share #3 Posted February 15, 2011 Hi The tolerances of too tight and too loose are pretty normal problems, the technicial has special tool for adjusting the spring, or he can replace, but I'd not bother unless you have a very heavy lens which 'dangles', under it own weight. Some lenses are out of tolerance by unresonable amount, most problems with newer M Leica lenses on old bodies, and CV LTM adapters on same bodies! Noel Link to post Share on other sites More sharing options...
earleygallery Posted February 15, 2011 Share #4 Posted February 15, 2011 It's normal - I suspect you are talking about a very minimal amount of rotational movement? I recall when the M8 was first released, lots of comments about how tight the lens mount was and in some cases lots of wear to the finish of the mount (down to the brass). I think Leica must have used a new design/tooling to incorporate the coding sensor, and the tolerances are much finer. Link to post Share on other sites More sharing options...
250swb Posted February 15, 2011 Share #5 Posted February 15, 2011 As I recall some of my lenses gave some movement on some cameras and not others. On my MP there is some movement from all my lenses, on my M9 there is some movement from some lenses. So I think its a combination of both camera and lens, not necessarily the body alone. Steve Link to post Share on other sites More sharing options...
lars_bergquist Posted February 15, 2011 Share #6 Posted February 15, 2011 The lens is locked by a spigot in the camera bayonet slipping into a slot in the lens bayonet. There must be a certain amount of play in order for this to happen. This does not affect performance the least. Focusing is a pure fore-and aft movement, and the bayonet spring ensures that the flange surfaces abut perfectly. You can in fact "over-rotate" the lens past the locking position, and with a film M this does not affect focus at all. Also, there is no coupling to transfer aperture info from the lens to the camera, so even such over-rotation cannot influence exposure. It has always been that way, and it was intended to be that way. It is so with my M4-P. My M8 was quite tight, but I suspect that the bayonet tolerances were written by somebody more theoretical than practical. My M9 is much more normal in this respect. So stop worrying. The old man from the Age of the M39x1 Screw Thread Link to post Share on other sites More sharing options...
jaapv Posted February 15, 2011 Share #7 Posted February 15, 2011 Advertisement (gone after registration) Uh-uh. On any lens but an 135 (which has an internal helicoid slope and a straight transferring lug) the roller will engage on a different part of the helicoid cam, causing a focussing error when overrotating to the stop. I agree that a slight play in the locking pin will be well within tolerance. Link to post Share on other sites More sharing options...
budrichard Posted February 15, 2011 Share #8 Posted February 15, 2011 Both my M7's have an infinitesimal amount of rock when a lens is mounted. Indeed I never noticed until I tried to move the lenses to confirm or deny this Thread.-Dick Link to post Share on other sites More sharing options...
fabphoto73 Posted February 15, 2011 Share #9 Posted February 15, 2011 Hi Keith, I had exactly the same with my new MP. Next to no resistance on mounting the lens and once clicked in place there was much more movement then any of my other bodies had. I had another MP, M6 and M8 to compare it to. I doubt very much that it would have effected focus or anything like that but to me it just didn't feel right so I sent it to Leica under warranty. Once they had received the camera this is what they told me : ******************************************************** Attn.: A little play between lens and camera is normal, but we have found out that the release button (release lens from camera) had to much play They fixed it and sent it back to me and now it is perfect. There is resistance (actually a bit more than my other MP and M6 now but about the same as my M8) when I mount the lens until it clicks in place and then it is solid as a rock. Hope this helps! Link to post Share on other sites More sharing options...
Keith (M) Posted February 15, 2011 Author Share #10 Posted February 15, 2011 Thank you all for the responses. It is beginning to look as though it is 'situation normal', However, it is a tad disconcerting initially to have such a marked difference in the ease of turning and locking the lens plus there being the very slight amount of rotational movement possible (by that I mean that it is not absolutely rock-solid unlike my M9). Maybe it is the M9 that is overly tight... Link to post Share on other sites More sharing options...
lincoln_m Posted February 15, 2011 Share #11 Posted February 15, 2011 Keith, Which lenses are you talking about, your Zeiss lenses or your Leica lens? I notice that my M2 has a very stiff mount, so much so it is difficult to turn all the way to lock position. I guess that could be spreading the bayonet fixing so that connection to my M7/MP may become looser? I'll double check over the weekend. It sounds like your M9 is a little stiff and your M7 is probably normal. You'll have users all over the world checking their mounts, a bit like the Leica lens aperture rattles we had recently. Regards, Lincoln Link to post Share on other sites More sharing options...
Keith (M) Posted February 16, 2011 Author Share #12 Posted February 16, 2011 Keith,Which lenses are you talking about, your Zeiss lenses or your Leica lens? I notice that my M2 has a very stiff mount, so much so it is difficult to turn all the way to lock position. I guess that could be spreading the bayonet fixing so that connection to my M7/MP may become looser? I'll double check over the weekend. It sounds like your M9 is a little stiff and your M7 is probably normal. Regards, Lincoln The situation is identical across all four lenses, of which the Summarit 75mm is the newest at barely a month old. I'm beginning to come round to the view that the M9 mount is on the tight-side but it will be interesting to compare the M7 against another M7. You'll have users all over the world checking their mounts, a bit like the Leica lens aperture rattles we had recently. I remember that - lots of suddenly worried people! Link to post Share on other sites More sharing options...
Xmas Posted February 16, 2011 Share #13 Posted February 16, 2011 Hi Keith The critical thing is does the latch seat itself every time, i.e. does the release button latching device bottom in the lens grouve. The lens can unscrew itself, just like a LTM lens but it only has a limited rotation before it drops off. You need to either watch the latch button seat or listen for its click. But if you dont like the M9 Leica will adjust it they wont want to leave it loose. If you dont like the M7 they can adjust or fit a new spring, but you need to be able to latch a lens with a limited rear ring only using the rear ring, otherwise the lens may dismantle, Leica lenses will 'self' dismantle, Zeiss (ZM) instruction manual says only use rear ring. My Ms have large differences in force required with Leica lenses and I needed to give away a CV adapter cause it did not allow all the release buttons to latch, reliabily. I think the release mechanisms were worn, and the adapter was within tolerance, the benificary says it is ok on his cameras. Noel Link to post Share on other sites More sharing options...
hamey Posted February 16, 2011 Share #14 Posted February 16, 2011 Just checked my M7 and the 35mm f2 asph, actually quite firm but not tight. Ken. Link to post Share on other sites More sharing options...
Shadow Blaster Posted February 17, 2011 Share #15 Posted February 17, 2011 Just checked my M7 with the 50mm Summilux ASPH and there's no movement, for what that's worth. Also checked my 24mm Elmar and 90mm Summicron AA with same result. Good luck, John S. Link to post Share on other sites More sharing options...
jrh68uk Posted February 17, 2011 Share #16 Posted February 17, 2011 Yep - both M7 and MP "knife through butter" as you put it but my M9 (and the M8 before it) noticeably tighter. FWIW, I prefer mounting on the M7 and MP as I feel I'm grinding metal a little too much with the M9 (never was a problem on the M8 in two years - just more noticeable scratches on the mounting surface of the camera). Link to post Share on other sites More sharing options...
andybarton Posted February 17, 2011 Share #17 Posted February 17, 2011 No movement on my M7 with a 35 ASPH or a '73 50 Summicron. Sorry... Link to post Share on other sites More sharing options...
menos I M6 Posted February 18, 2011 Share #18 Posted February 18, 2011 My M8.2 fits without any movement with any lens at all. My M7 has the slightest bit of play, but only with certain lenses. Important lenses, like the 90/2 or 50/1 sit really tight, which is necessary for their heavier focus action. My M6 classic is more loose and even the Noctilux and 90/2 wiggle slightly perceivable. The most loose in the crop is my EPSON R-D1, which resides mostly in storage these days. I would suggest, that Leica tightened the mount precision as well, to increase performance through all possibilities for reaching the necessary tolerances for the more demanding sensor. Link to post Share on other sites More sharing options...
Xmas Posted February 18, 2011 Share #19 Posted February 18, 2011 I would suggest, that Leica tightened the mount precision as well, to increase performance through all possibilities for reaching the necessary tolerances for the more demanding sensor. Hi Menos It is the M7 with the less demanding tolerances that is not so tight. The mount precision is not altered by the tension, unless it were really slack, so that the lens were able to move along the axis away from the registration plate. Any good repair person should be able to adjust the tension. Noel Link to post Share on other sites More sharing options...
menos I M6 Posted February 18, 2011 Share #20 Posted February 18, 2011 Hi Menos It is the M7 with the less demanding tolerances that is not so tight. The mount precision is not altered by the tension, unless it were really slack, so that the lens were able to move along the axis away from the registration plate. Any good repair person should be able to adjust the tension. Noel Noel, that is exactly, what I meant to describe - my M7 allows, to slightly rotate the lens, when properly mounted. Also, mounting a lens is easier on the M7 - less strength is needed, to lock the lens into position and the mount is not as tight (inner dimensions), which can be observed, , when mounting LTM lenses with certain Voigtlander LTM-M adaptors. These LTM lenses can be mounted with ease, while on the M8.2, they are more difficult to position and insert. I wrote, that I suppose, that Leica tightened the overall tolerances of all involved measurements in the assembly, which potentially are involved in precision of lens to sensor. My M6 is even "more loose", than the M7. Link to post Share on other sites More sharing options...
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