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12-01-2012, 04:55 PM   #1
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Video mode and manual shutter speed/ISO ?

Hi.
Is there no way to lock the shutter speed/ISO when using M lenses in video mode?

Manual mode works fine with A series but with M series it seems to attempt to auto expose by adjusting shutter speed.
TIA,
art

12-01-2012, 10:31 PM   #2
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I think you can force the exposure to stay the same by setting the exposure setting in the movie menu to M.

Just tried it and that is what it seems to do.

edit: also tried it in AV mode.. seems to stay put just like in M mode. P mode does seems to try to change the exposure while recording.

Last edited by cyclone3d; 12-01-2012 at 10:38 PM.
12-01-2012, 10:49 PM   #3
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QuoteOriginally posted by cyclone3d Quote
I think you can force the exposure to stay the same by setting the exposure setting in the movie menu to M.

Just tried it and that is what it seems to do.

edit: also tried it in AV mode.. seems to stay put just like in M mode. P mode does seems to try to change the exposure while recording.
Are you using an M series lens? With A and later series it works as expected but with M series lens and exposure mode M mine is changing exposure.
12-02-2012, 01:17 PM   #4
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OK, found exposure lock works in video mode. So if you use an M lens in video mode and dont want autoexposure to mess up your moving shot, you can set Av mode and then hit the exposure lock. This will keep the exposure from changing during pan/tracking shots. The problem here is that the camera doesnt show the shutter speed, so you dont know what you are shooting at (is is it really that complicated for firmware to just display the current shutter speed in Av movie mode?) .

So the bottom line seems to be that there is no manual exposure mode when using M series lenses in video mode. In Av you can lock the exposure but the camera doesnt tell you what shutter speed you are shooting at.

Real bummer if you were planning on video with a collection of M series glass.
Regards.

12-03-2012, 10:49 AM   #5
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QuoteOriginally posted by alamm001 Quote
Are you using an M series lens? With A and later series it works as expected but with M series lens and exposure mode M mine is changing exposure.
Tested it with both my FA 50mm 1.4 and also a converted Konica Minolta 58mm 1.4 (which is full manual).
12-05-2012, 11:02 AM   #6
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Weird that it works on your conversion lens. Heres a link to a video I uploaded earlier illustrating the problem.

12-11-2012, 06:23 AM   #7
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I'm afraid I don't do enough video to fully grok the problem, but I'm thinking the problem is because the M lenses don't report their range of apertures to the camera (Like A-series lenses), so it's doing a best guess - and not guessing well. The comment about the Konica makes me wonder if it works better when it can't adjust the aperture at all - have you tried with an even older M42 lens?
12-11-2012, 06:33 AM   #8
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Do you have the ISO locked in also?

12-11-2012, 08:33 AM   #9
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QuoteOriginally posted by THoog Quote
...because the M lenses don't report their range of apertures to the camera (Like A-series lenses), so it's doing a best guess -and not guessing well. The comment about the Konica makes me wonder if it works better when it can't adjust the aperture at all - have you tried with an even older M42 lens?
Well it really shouldnt be guessing/changing anything in manual mode.It should ideally allow me to make the choice of shutter speed (within FPS limit) and ISO and hold those values.

I wish I had some screw mount lenses to test but I dont unfortunately.

The Konica behaviour is really strange, unless the conversion was to Fa mount. I believe I tested a couple A series lenses with the aperture rings off 'A' (ie: on F-Stops) and it worked corectly which is weird. Its supposed to behave like a manual aperature lens on off the 'A'.


@malbers: yes, auto ISO is off in that video test.

Last edited by alamm001; 12-11-2012 at 08:35 AM. Reason: spelling correction
12-11-2012, 08:59 AM   #10
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Well, for stills, the K-01 behaves a little differently for K/M lenses because it holds the aperture open for focusing. I found that I actually like the M42 behavior better in Manual+AutoISO mode, so I put a little celo tape on the lens mount to make the camera treat it like an M42. I wonder if that might be a workaround for your problem as well...
12-12-2012, 04:49 AM   #11
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QuoteOriginally posted by THoog Quote
Well, for stills, the K-01 behaves a little differently for K/M lenses because it holds the aperture open for focusing. I found that I actually like the M42 behavior better in Manual+AutoISO mode, so I put a little celo tape on the lens mount to make the camera treat it like an M42. I wonder if that might be a workaround for your problem as well...
Thanks THoog. Due to your post, I have found that AE-L also works when you set ISO-Auto in M mode and it reports the shutter speed! It doesnt report the ISO but its better than AE-L+Av mode.

So to summerize my findings:

1) Movie mode M, ISO manual = AE-L does not function - you have auto exposure no matter what you do.
2) Movie mode M, ISO auto = AE-L works - shutter reported, ISO not reported.
3) Movie mode Av, ISO unavailable = AE-L works - shutter not reported, ISO not reported.

I can definietly live with two.
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