My M4 shutter gets sticky if it has been cocked for a while, but normal if cocked and release immediately

[Greenhilltony]

Advertisement (gone after registration)

My M4 begins to suffer from a weird problem. One day I loaded a roll of film, did not open the back door to check if the film was flat and pushed deeply enough to sit right behind the shutter curtains. I advanced and fired once, advanced again and then it stuck. The advance was incomplete and the shutter could not be released. I rewound it and took it out, then I saw one sprocket on the upper side of the film got folded, which could be jammed by the shutter. I carefully inserted the film in again, this time seemed fine. But then I noticed the issue: If I wind the lever, leave it for a while, and then release the shutter, it does not sounds like the speed I set to it: e.g., I set 1/500s, but it sounds like 1/30. The images taken at these moments both show overexposure on the right 2/3 of the frame. Shots taken immediately after this “sticky” shot are normal, without uneven exposure or inaccurate speeds.

The other day, I wounded and released the shutter without loading film for a while, almost equivalent to 4-5 rolls of film. Then I loaded another two rolls of film, finished them and developed at home. The shutter sounds did not fall to 1/30 when I left it cocked for several minutes to half an hour; still it sounds like 1/125 when I set it to 1/500. The uneven exposure became less significant on the image, but still observable. 

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

I searched for this problem for a while but could not find another one with the exact issue of mine. I took some slow-mo videos with my iPhone to examine the shutter actions at speed above 1/50. It seemed the second curtain could not catch up with the first when they reached the middle position. I tightened the second curtain with back-and-forth adjustments. Before the adjustment, when set to 1/500, I thought the curtains left a space for 1/125 when the shutter opened to 1/3 of the distance. After the adjustments the gap got narrower but still not very even from the beginning to the end.

[Advertisement]

The Leica Q3 is available for pre-order at B&H Photo Video and Adorama

[Greenhilltony]

Images of shutter curtains movements at 1/500s

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

[jakontil]

All i can say is, it’s probably need a good CLA

[hansvons]

52 minutes ago, jakontil said:

need a good CLA

Yes. Leica M film cameras have an excellent reputation as reliable workhorses. But back in the day when they earned that reputation in demanding journalism, a CLA was a regular. Every 500 rolls or so a CLA is due. Sitting on the shelf is even worse. Mostly it’s about replacing the grease of the precision mechanics which gets sticky over time. 

[01af]

vor 5 Stunden schrieb jakontil:

... it probably needs a good CLA

Replace 'probably' with 'desperately.'

[jakontil]

28 minutes ago, 01af said:

Replace 'probably' with 'desperately.'

From where I’m from, we are used to downplay statement as not to scare him away 😂🤣😂🤣 joke aside 

but seriously to OP, definitely CLA and services… the time spent on shooting is worth more than anything involved

[spydrxx]

Advertisement (gone after registration)

Don't fight it, don't think it is a do-it-yourselfer. Get a CLA by a well known professional used to doing Leica CLAs, and enjoy years of trouble free shooting with your M4. It is a great camera when everything works as it should. It was the only Leica camera I bought new and it went almost 30 years before needing a CLA, and then only because I dropped it.  

[Greenhilltony]

17 minutes ago, spydrxx said:

Don't fight it, don't think it is a do-it-yourselfer. Get a CLA by a well known professional used to doing Leica CLAs, and enjoy years of trouble free shooting with your M4. It is a great camera when everything works as it should. It was the only Leica camera I bought new and it went almost 30 years before needing a CLA, and then only because I dropped it.  

Indeed I know the masters in my place, and I have paid visits to one of them for a few times and learned a lot joyful facts and knowledge about Leica. What upsets me is this M4 was claimed to just received a CLA before selling to me, and I easily got it ‘broken’ when I followed the instructions of loading illustrated on the base: pull the strip to the prong, push the film and strip inside, close the baseplate—but it failed to guide the film onto the correct plane but let it jam the shutter instead. It is absolutely a lesson, but I didn’t think it would be necessary.

[Greenhilltony]

23 minutes ago, spydrxx said:

Don't fight it, don't think it is a do-it-yourselfer. Get a CLA by a well known professional used to doing Leica CLAs, and enjoy years of trouble free shooting with your M4. It is a great camera when everything works as it should. It was the only Leica camera I bought new and it went almost 30 years before needing a CLA, and then only because I dropped it.  

One more thing: When I wind the advance lever, it needs a bit extra force to push it to the end. When I open the back gate, I see it is that last bit of extra force to bring the shutter curtain fully over the underneath one. I have no experience with other film M. The advance lever on my Minolta CLE, and the other manual advance cameras, do not have this kind of two-level force feeling when advance. Though I think my M4 advance is smooth, I am curious.

[hansvons]

No extra force should be needed. Cocking the shutter and transporting the film should be a smooth, highly satisfactory experience in one go. I speak from M4-P and M6 experience. 

[TomB_tx]

The shutter curtains are the most delicate part of the camera. A film edge/end getting caught between the curtains or in the mechanism can cause your issues. This is not unique to Leica - but to any camera with cloth focal plane curtains. I've seen Barnack cameras and clones damaged where the user didn't bother to cut the required "long leader" and tried a faster method, but the film edge buckled or caused damage.

That's another reason I always rewind a film fully into the cassette, leaving no tongue sticking out. Otherwise if someone trips the shutter that hanging leader could catch the shutter. I once found a piece of a film leader rolled in the shutter of a used camera I bought.

[Huss]

15 hours ago, hansvons said:

Yes. Leica M film cameras have an excellent reputation as reliable workhorses. But back in the day when they earned that reputation in demanding journalism, a CLA was a regular. Every 500 rolls or so a CLA is due. Sitting on the shelf is even worse. Mostly it’s about replacing the grease of the precision mechanics which gets sticky over time. 

Every 500 rolls?  Ms are built to be used, which is why those sitting have issues.  500 rolls is just getting warmed up.

[jerzy]

A bit more force at the end of wind cycle is a normal thing with M. Simplifying - at the end of cycle a latch preventing accidental release is de engaged. If you try to release before this last step it will not work, you will have impression that shutter is jammed. CL has it solved differently, you do not need this extra force.

the other problem as you described points rather to a sticky curtain, opening curtain. You cannot damage camera in this way by not correct film loading. So, as indicated - either CLA or return

[Bronco McBeast]

On 8/23/2023 at 1:42 AM, hansvons said:

Yes. Leica M film cameras have an excellent reputation as reliable workhorses. But back in the day when they earned that reputation in demanding journalism, a CLA was a regular. Every 500 rolls or so a CLA is due. Sitting on the shelf is even worse. Mostly it’s about replacing the grease of the precision mechanics which gets sticky over time. 

“Back in the day”,  believe me, 100 rolls could be shot in one day. And 700 rolls im a single week, for weeks. And 20-40 rolls per day was a Base standard.

”back in the day”, a Cla was needed exactly when it was meeded, not before, and it usually happened once per decade at a rate of at least 100 rolls per week, which comes down to around  52,000 rolls of film.

[Bronco McBeast]

On 8/23/2023 at 5:01 PM, Huss said:

Every 500 rolls?  Ms are built to be used, which is why those sitting have issues.  500 rolls is just getting warmed up.

Not even warmed up. I used to shoot 500 in a month. Now it’s 500 im a year, and it’s not even warmed up. At least, I don’t feel my Leicas to be watmed up. My now 15 years old MP feels warmed up but my 10 years old MP does not fwwl warmed up yet, and they both go through my shooting cycle of several more cameras...

[Tom R]

I had a very similar problem with a newly CLA'd M4-P recently. I had the small curtain replaced, but the problem returned shortly thereafter. I sent the unit back to the original technician and it turned out that the master roller needed replacement! I'm putting roll through that camera today and we'll see if that fixed the problem.

[Bronco McBeast]

Anecdotally, Nikon rfs seemed to simply NEVER neeed a CLA, no matter the quantity of use

Edited August 25, 2023 by Bronco McBeast
Typos

[Greenhilltony]

Put it down to a master today. He checked and found the shutter curtains are going to “melt” so they got sticky. The curtains seemed to have been torn apart and sewn together, and he thought my M4 gave unusually loud shutter sound because the curtains were over tightened. He offered me the replacement of the curtains and by the way a full CLA. Looking forward to a properly CLA’d M4 and feel how smooth it would be!

[Advertisement]

Hallo,

Look here: Leica M

[Greenhilltony]

8 minutes ago, Tom R said:

I had a very similar problem with a newly CLA'd M4-P recently. I had the small curtain replaced, but the problem returned shortly thereafter. I sent the unit back to the original technician and it turned out that the master roller needed replacement! I'm putting roll through that camera today and we'll see if that fixed the problem.

Very similar reason—the aging of the curtains of a camera as old as my parents. Luckily the master I went for today has a very solid reputation among Hong Kong Leica users. He promised me a complete check of the gears and even a cleaning of the viewfinder.