m mount doesn't lock in place

[fjmcsu]

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Recently I noticed that none of my lenses lock in place when threading them onto the body. Usually they would lock in place but now they will just as easy screw out without pressing the lock button. There is enough play that the sensor will not read the coded lenses if I don't have it correctly seated.Is there some manual adjustment I can make to allow the locking mechanism to work or does this mean a trip to the repair shop?

[ho_co]

Francisco, there's no adjustment that I'm aware of.

 

If you look at the camera bayonet, you'll see that the back portion of it is slightly sprung. That is, each lug of the bayonet is bent back into the body and serves as a spring to hold the lenses in place.

 

I don't think I've ever heard of a Leica bayonet loosening up as you describe, though I think there was one forum member who had mounted a lens improperly and had to return her camera for some kind of adjustment.

 

If the lens isn't held firmly against the body, the rangefinder may not be coupling accurately, and the lens may be cocked, tighter on one side than on the other. Either of those could cause noticeable image unsharpness.

 

I'd have it checked.

 

--HC

[Shootist]

Recently I noticed that none of my lenses lock in place when threading them onto the body. Usually they would lock in place but now they will just as easy screw out without pressing the lock button. There is enough play that the sensor will not read the coded lenses if I don't have it correctly seated.Is there some manual adjustment I can make to allow the locking mechanism to work or does this mean a trip to the repair shop?

 

First off the Leica M lenses, or any lens specifaclly made for the M series of cameras, do NOT screw in or out. They are a Twist Lock mount. The twist lock movement is only about a 1/4 turn or less, more like 1/8 turn

If you are screwing lenses in and out, IE several turns around (or just more then 1/8 turn), then you have LTM lenses and the LTM to M mount adapter is stuck in the camera, or maybe not stuck but not coming out with the lens.

Could be you locked up the adapter by turning it to far when installing a lens and holding down on the buttom (tip, don't hold the button down when you are putting a lens on the camera. Just wait to hear it CLICK in) and then when you went to take a LTM lens out the adapter stayed in the camera even though you pushed the button.

Please check that and post back.

[fjmcsu]

thanks for all your responses. The M8 i've had since about April. & the lenses are all new & coded. I have always noted they clicked in place as you noted after a small turn. As of yesterday I noted no click at the end of the "turning " of the lens. The lens turns in nice & flat & is in normal flush position.I can turn the lens to the appropriate position to take it off(red dot marker to unlocking button) WITHOUT pressing the release button.Again as if the lens is not locking in place or the (un)locking button is not working. This occurs with all my lenses now(75 lux, Elmarit 28, Noctilux etc)

[jaapv]

First check if there is not a piece of gunk in the release button mechanism. It happens.

[fjmcsu]

Jaap,

It appears that the unlocking mechanism does not "spring" back out once the lens is turned onto the bayonet. I can manually(using a very thin small screw driver tip) pop it into place.Without the lens in place the button does not spring out-ward unless I gently push it out with aforementioned screw driver.I can't se anything stuck around the button & tried compressed air into the area between the button & collar! The button has some sprint to it but as you stated there must be something holding it from back springing out -ward.

[ho_co]

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Francisco--

I'm glad for your discovery! Ignore my dire prediction of a damaged bayonet.

 

Could be a broken or bent spring. Mark Norton's post on getting to the lens-retaining spring might help: http://www.l-camera-forum.com/leica-forum/leica-m8-forum/26771-sudden-problem.html#post279972.

 

Elsewhere Mark has given instructions for removing the top plate: http://www.l-camera-forum.com/leica-forum/leica-m8-forum/32824-question-mark-norton-m8-vertical-adjustment.html#post344834.

 

--HC

[ho_co]

First off the Leica M lenses, or any lens specifaclly made for the M series of cameras, do NOT screw in or out. They are a Twist Lock mount....

More accurately referred to as a "bayonet mount."

 

Or as a verb: "The lens bayonets in place."

 

Better: "When I try to mount the lens...," etc.

[fjmcsu]

Francisco--

I'm glad for your discovery! Ignore my dire prediction of a damaged bayonet.

 

IIRC, Mark Norton has published somewhere on the forum a quick treatise on removing the pop-up lock mechanism to clean it or replace the spring under it. I'll look to see if I can find it.

 

--HC

Thanks & it appears that is what needs to be done. I will try to find it also.

[ho_co]

Francisco--

Recheck my post above. I found both the links you need. I hope it helps, but I'm too clumsy to attempt it on my M8.

 

--HC

[fjmcsu]

Thanks. I did miss your links, but checked them out.Since the lenses sit fine it appears to be the unlocking button spring perhaps has fallen away or is stuck.I will probably take it to the dealer & let them repair it as soon as I receive my Nikon D3 .

[marknorton]

It sounds like the lens release button is binding. There's a spring behind the button and a spigot which passes through the casting, secured by a circlip on the reverse side (circled).

 

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It's a big job to fix, the top and back have to come off, then the sensor and the shutter.

 

Worth checking whether it's actually the "finger" (with the red dot) which is binding to the lens mount or it really is the button itself. Certainly (if there are others reading this in the future and your camera is out of warranty), you might find using the smallest amount of fine oil, worked into the part which is binding will help. Otherwise, it will be an expensive repair.

[Shootist]

Mark looking at both my M8's it looks like there is a screw on top of the lens lock/release button just like on the frame selector lever, BUT it would take a special wrench, something similar to this,

 

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or a flexclamp with a extended collar, again something special, to get down inside the shroud that surrounds it.

 

Are you saying you have to take the whole camera apart to get to the spring underneath the lens lock/release button. That seems completely STUPID.

[marknorton]

Ed, afraid so, to release the button, you have to remove the circlip on the back. I did take it apart when I dismantled my M8 but didn't take a picture because I never thought anyone would be interested! The same major surgery (more, actually) is required to replace the strap eyelets.

[Shootist]

Ed, afraid so, to release the button, you have to remove the circlip on the back. I did take it apart when I dismantled my M8 but didn't take a picture because I never thought anyone would be interested! The same major surgery (more, actually) is required to replace the strap eyelets.

I would expect it for the strap eyelets but to change/replace a small spring on a part that is used all the time is totally ridiculous.

Does that top part even come off, IE the one that looks like a Leica "F the user so he may need aspecial wrench" screw similar to the one on the frame selector lever, or does the actual button/locking lug slip off the bottom of the stud?

 

EDIT:

Mark from looking at your pictures of the EXPLODED M8 it seems you can get to that circleclip without taking the sensor board and shutter out, although it does look like a tight fit to get in there. Maybe not to take the clip off but certainly to put it back on.

[marknorton]

The black surround is part of the casting, the chromed button is one piece with a spigot which passes through the coil spring, then through a hole in the casting to be secured by the circlip. So the order of parts is button, coil spring (under compression), casting, circlip.

[robsteve]

The black surround is part of the casting, the chromed button is one piece with a spigot which passes through the coil spring, then through a hole in the casting to be secured by the circlip. So the order of parts is button, coil spring (under compression), casting, circlip.

 

Mark:

 

The head of the button unscrews. Mine came loose when I first got the M8. Ed's description of a special tool to tighten or remove is probably correct. I don't think it is any different than the normal film M. I have had the button come loose on them too. I tend to hold the lens and twist the camera when releasing a lens and this must cause my finger to put unscrewing pressure on the button.

 

Robert

[Shootist]

Mark:

 

The head of the button unscrews. Mine came loose when I first got the M8. Ed's description of a special tool to tighten or remove is probably correct. I don't think it is any different than the normal film M. I have had the button come loose on them too. I tend to hold the lens and twist the camera when releasing a lens and this must cause my finger to put unscrewing pressure on the button.

 

Robert

 

So Rob you are saying that IS a screw on the lens lock/release button and it CAN be taken out WITHOUT taking the camera apart??? Correct???

 

I would of thought so.

Mark it is to bad you didn't take pictures of the lens lock/release button when you had it out. I would also think that Leica isn't that stupid because IF that spring brakes during the warranty period it would cost them, Leica, a lot to repair a $0.10 +/- part.

[robsteve]

So Rob you are saying that IS a screw on the lens lock/release button and it CAN be taken out WITHOUT taking the camera apart??? Correct???

 

I would of thought so.

Mark it is to bad you didn't take pictures of the lens lock/release button when you had it out. I would also think that Leica isn't that stupid because IF that spring brakes during the warranty period it would cost them, Leica, a lot to repair a $0.10 +/- part.

 

Mark may be right about the spring. I think it was just the post the lens release locking tab goes on that was visible, not a spring.

 

If you could not remove this locking tab by unscrewing the the release button, it would be impossible to take the lens mounting ring off without taking the whole camera apart.

 

Robert

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Hallo,

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[Shootist]

Mark may be right about the spring. I think it was just the post the lens release locking tab goes on that was visible, not a spring.

 

If you could not remove this locking tab by unscrewing the the release button, it would be impossible to take the lens mounting ring off without taking the whole camera apart.

 

Robert

So the spring might be internal but yet the actual locking tab can come off.

Well I'll have to make (fudge) or order a tool to take that screw out.