Mp-shutter Sound

[ian moore]

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Just recieved my new MP,0.72. I notice that the shutter makes a whirring sound at speeds slower than 1/8th.

 

My M7 doesn't make this sound. Is this normal or should I return to supplier?

 

Thanks for views.

 

Ian.

[lambroving]

Probably just fine. Your M7 shutter speeds are governed electronically.

[treeplanter]

Just recieved my new MP,0.72. I notice that the shutter makes a whirring sound at speeds slower than 1/8th.

 

My M7 doesn't make this sound. Is this normal or should I return to supplier?

 

Thanks for views.

 

Ian.

 

As William just implied, the MP has a mechanically-governed shutter, meaning that the slow speeds are governed by cams, gears and springs, which accounts for the whirring noise you hear.

 

To me, old-fashioned guy I am, that sound is music.

 

Jim Bielecki

[TimF]

Yep, perfectly normal.

 

I'm with Jim, its part of the charm of a mechanical Leica, just like the "Contax wheeze".

[Guest leica_mage]

To be more specific: between 1/1000 and 1/50 (flash synch speed), you get a "normal" sound (but what a sound!).

 

At 1/30 and 1/15, you get the shutter sound plus what sounds like little ball bearings dropping and bouncing inside the camera.

 

Between 1/8 and 1 you get the whirring / wheezing, etc.

 

The explanation was furnished by Jim - and I'm with him about the music. It is indeed music. Like no other shutter sound. Once you're hooked on it, all other cameras sound like rifles.

 

Best, and enjoy the lovely MP. Mine is coming this week!!

[adan]

To be even MORE specific: From the sync speed (1/50) up, the exposure time is governed by the width of the slit between the curtains (in both the M7 and the MP). At 1/50th the 'slit' equals the full 36mm width of the frame (thus allowing a brief flash to hit all the film at once).

 

For longer exposure times, the MP (and all previous mechanical Leicas) have an escapment mechanism that holds back the second curtain for the appropriate amount of time, and then releases it. The M7 uses an electromagnet to hold back the second curtain, and just counts electrons silently to measure the time.

 

The whirring you hear DURING the exposure is the escapment unwinding to the release point. The whirring you hear AFTER the exposure is the escapment clockwork resetting itself (running backwards).

 

At 1/30 and 1/15 a different, faster escapment is used, with fewer gears, and so the release and resetting sounds are faster (the "bouncing ball-bearing" sound).

 

If you look into the front of a mechanical Leica M with the lens off and shoot at a long exposure time, you can see the second curtain creeping up to the edge of the frame, fighting against the gears holding it back, and then - zip - it goes across. (Too much creep is a sign the camera is due for adjustment).

[Guest leica_mage]

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To be even MORE specific: From the sync speed (1/50) up, the exposure time is governed by the width of the slit between the curtains (in both the M7 and the MP). At 1/50th the 'slit' equals the full 36mm width of the frame (thus allowing a brief flash to hit all the film at once).

 

For longer exposure times, the MP (and all previous mechanical Leicas) have an escapment mechanism that holds back the second curtain for the appropriate amount of time, and then releases it. The M7 uses an electromagnet to hold back the second curtain, and just counts electrons silently to measure the time.

 

The whirring you hear DURING the exposure is the escapment unwinding to the release point. The whirring you hear AFTER the exposure is the escapment clockwork resetting itself (running backwards).

 

At 1/30 and 1/15 a different, faster escapment is used, with fewer gears, and so the release and resetting sounds are faster (the "bouncing ball-bearing" sound).

 

If you look into the front of a mechanical Leica M with the lens off and shoot at a long exposure time, you can see the second curtain creeping up to the edge of the frame, fighting against the gears holding it back, and then - zip - it goes across. (Too much creep is a sign the camera is due for adjustment).

Andy, splendid and masterful!

 

Best,

[Confusion Circle]

Thank-you for that explanation!