[bug] shutter speed in burst mode

[Photoworks]

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6 hours ago, geotrupede said:

high speed burst

mechanical shutter

no flash

no lens coding

manual exposure

manual iso

visoflex with the live view on

1/15th set in the dial

saved to card

dng

low res 18MP

etc.

most pics are 1/15th as set but some 1/100th and obviously underexposed. and that is how I realised this, by finding darker frames within the same sequence which is certainly not me changing the shutter speed and then putting it back on within a burst...

anyway, seems it could be a bug / limitation of the up/down/up/down shutter movement in combination with live view, etc.

provided the camera does not break I am fine with the bug,

G>

 

I just did the test with your setting and same SD card. No problems here in over 100 frames.

 

I better reset camera to 60MP before I start shooting my staff in 18MP LOL

[orcinus]

If the affected burst pics really are taken at 1/15, and it's not just a metadata artifact, then i might have an idea about what's causing it.

There's an issue ("a feature, not a bug") with the shutter dial's construction - it's not a selector switch but an encoder (cheaper and easier to implement) using some form of gray's code to decode position into shutter speed. When it's not sitting *quite* on the mark, and is in between two values, it will seem to "fall back" to the nearest upper bit shutter value.

I've demo'd it in this video:

 

Now, in normal use, this will likely never happen, but if the encoder on your particular sample is faulty, or the encoder and the knob are slightly misaligned, or there's oxidation on the contacts, or who knows what else, you might experience what you're experiencing due to vibration, accidentally brushing the knob with your finger etc.

[Photoworks]

8 hours ago, orcinus said:

Now, in normal use, this will likely never happen, but if the encoder on your particular sample is faulty, or the encoder and the knob are slightly misaligned, or there's oxidation on the contacts, or who knows what else, you might experience what you're experiencing due to vibration, accidentally brushing the knob with your finger etc.

Isn't this video old, it was already fixed in firmware  a long time ago.

[orcinus]

6 hours ago, Photoworks said:

Isn't this video old, it was already fixed in firmware  a long time ago.

It is old, and it wasn't fixed, because it's not a firmware issue.
Newer firmwares do a better job of filtering it to a degree, but it still happens.

I can still reproduce it on mine, for a couple of spots on the dial.

On a faulty or noisy or out of spec camera, it's entirely feasible to expect it happening more often.

[mrmalo]

23 hours ago, geotrupede said:

high speed burst

mechanical shutter

no flash

no lens coding

manual exposure

manual iso

visoflex with the live view on

1/15th set in the dial

saved to card

dng

low res 18MP

etc.

most pics are 1/15th as set but some 1/100th and obviously underexposed. and that is how I realised this, by finding darker frames within the same sequence which is certainly not me changing the shutter speed and then putting it back on within a burst...

anyway, seems it could be a bug / limitation of the up/down/up/down shutter movement in combination with live view, etc.

provided the camera does not break I am fine with the bug,

G>

 

Reminds me of a similar issue an M11 user had with "Continuous - Low Speed" which was over exposing the odd frame in a burst.

Video of the problem:

Original forum post about the issue:

Is this the sort of thing you're seeing (but in continuous high speed with under exposed images)?

[geotrupede]

12 minutes ago, mrmalo said:

Reminds me of a similar issue an M11 user had with "Continuous - Low Speed" which was over exposing the odd frame in a burst.

Video of the problem:

Original forum post about the issue:

Is this the sort of thing you're seeing (but in continuous high speed with under exposed images)?

yes same issue but reverse in the fact that the odd frame is a faster exposure at 1/100th.

as for the contact on the dial, indeed if one moves the dial between marks the exposure goes to infinity (not infinity really but something long)

whatever this is, it is erratic, last night I tested 270 frames and was all ok. so not sure.

it did happen 10 times the day before within 30 minutes or so shooting at the pub.

the distance between the odd frames was not constant, the whole thing is very random

G.

 

 

[geotrupede]

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after contacting Leica I understood this being a bug, the solution should be to reset the camera, which I did. Will update if the issue persists but hopefully it is now resolved. If anyone else has this odd exposure here and there, fist step, reset camera. You can recall the profiles so it is not too bad.

G>

 

[DenverSteve]

It may not help but when any occasional anomalous activity happens, I do a reset and, usually, that takes care of it.  Although, that doesn't explain why it happened. 

[geotrupede]

well, the fact is that a shutter moving in disagreement, and quickly through a burst, with the set speed is worrisome: who can say it would not break? a software malfunction may result into physical damage... I hope that the issue has not reduced the life of the shutter nor compromised it...  

time will tell, hopefully, not 😉

G