When to disable the 'Shutter'? at DVinfo.net

James Kuhn · July 18th, 2013, 12:29 PM

Being new to 'video' (though, Stills background), could someone please explain "why and when" it's appropriate to turn the 'Shutter On or Off'? As I understand it, when a video camera 'Shutter' is disabled, the 'Shutter-Speed' reverts to the 'Frame-Rate'? For example, if you're shooting 30 fps (29.97 fps) the 'effective Shutter-Speed' is ~1/30th.

Please feel free to correct me, I'm a little shaky on the 'facts'.

Thanks,

J.

Brian Drysdale · July 18th, 2013, 02:17 PM

The shutter isn't required when shooting interlace video, but when shooting progressive you get a smearing on action when the shutter is switched off. One reason for not using the shutter is obtaining exposure low light levels, however, this has tempered by the "ghosting" effect on the action.

For a normal use the optimum shutter speed is usually about temporally half that of the frame rate e.g 1/60 for 30 fps.

James Kuhn · July 18th, 2013, 07:15 PM

Thanks Brian!

I shoot primarily in 'progressive', so, I haven't had the need to turn-off the 'shutter'. I understand the issue of ghosting when 'dragging the shutter', i.e., 'motion-blur'.

So, it's primarily a 'progress/interlace thing'? Are there any 'creative' reasons to 'not use shutter', beyond 'motion-blur'?

I appreciate your insight.

Regards,

J.

Brian Drysdale · July 19th, 2013, 01:19 AM

Apart from the blurring, there's no creative reason other than wanting the extra DOF because you usually gain a stop when not using the shutter, although these days the problem is often trying to ND the sensitive sensors.

It's worth doing a test to see the effect.

James Kuhn · July 19th, 2013, 08:43 AM

Brian...again, thank you for the thoughtful response. I'm all about 'testing', but did not understand the practical use for disabling the Shutter.

Regards,

J.

July 18th, 2013, 12:29 PM	#1
James Kuhn Major Player Join Date: Sep 2011 Location: Merritt Island, Florida Posts: 865	When to disable the 'Shutter'? Being new to 'video' (though, Stills background), could someone please explain "why and when" it's appropriate to turn the 'Shutter On or Off'? As I understand it, when a video camera 'Shutter' is disabled, the 'Shutter-Speed' reverts to the 'Frame-Rate'? For example, if you're shooting 30 fps (29.97 fps) the 'effective Shutter-Speed' is ~1/30th. Please feel free to correct me, I'm a little shaky on the 'facts'. Thanks, J. Last edited by James Kuhn; July 18th, 2013 at 12:30 PM. Reason: corrected misspelling.

July 18th, 2013, 02:17 PM	#2
Brian Drysdale Inner Circle Join Date: Feb 2006 Location: Belfast, UK Posts: 6,143	Re: When to disable the 'Shutter'? The shutter isn't required when shooting interlace video, but when shooting progressive you get a smearing on action when the shutter is switched off. One reason for not using the shutter is obtaining exposure low light levels, however, this has tempered by the "ghosting" effect on the action. For a normal use the optimum shutter speed is usually about temporally half that of the frame rate e.g 1/60 for 30 fps.

July 18th, 2013, 07:15 PM	#3
James Kuhn Major Player Join Date: Sep 2011 Location: Merritt Island, Florida Posts: 865	Re: When to disable the 'Shutter'? Thanks Brian! I shoot primarily in 'progressive', so, I haven't had the need to turn-off the 'shutter'. I understand the issue of ghosting when 'dragging the shutter', i.e., 'motion-blur'. So, it's primarily a 'progress/interlace thing'? Are there any 'creative' reasons to 'not use shutter', beyond 'motion-blur'? I appreciate your insight. Regards, J.

July 19th, 2013, 01:19 AM	#4
Brian Drysdale Inner Circle Join Date: Feb 2006 Location: Belfast, UK Posts: 6,143	Re: When to disable the 'Shutter'? Apart from the blurring, there's no creative reason other than wanting the extra DOF because you usually gain a stop when not using the shutter, although these days the problem is often trying to ND the sensitive sensors. It's worth doing a test to see the effect.

July 19th, 2013, 08:43 AM	#5
James Kuhn Major Player Join Date: Sep 2011 Location: Merritt Island, Florida Posts: 865	Re: When to disable the 'Shutter'? Brian...again, thank you for the thoughtful response. I'm all about 'testing', but did not understand the practical use for disabling the Shutter. Regards, J.