Shooting TV, Computer Monitors etc. eliminate flicker?

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What do I need to do to be able to DV shoot a computer monitor so the flicker from monitor scan doesn't show.

-- Ted Karet (tkdencol@yahoo.com), February 21, 2001

Answers

TV monitors are no problem as long as you are shooting NTSC off an NTSC monitor or PAL off a PAL monitor. If you are in the US shooting off a US TV...don't worry about it. Computers are another thing altogether. High-end Pro cameras have a clear-scan feature which allows you to dial in the scan rate to match that of the computer. Short of that the only other option you have is to try to match the camera's shutter speed to the computer scan rate as close as possible. If you can set the computer's scan rate at 60 Hz. that would be perfect. I can't do that on the Imac in front of me, but I can set it to 1024x768 @ 75Hz. and set the camera's shutter speed at 1/15th which is a multiple of 75 and get a clean image.

-- Tim Courlas (timc@horizonscompanies.com), February 21, 2001.

You could also try using a video projector, projecting the footage onto a screen and shooting it.

-- -- Eric Melrose (emelrose@bit-by-bit.com), August 26, 2001.

I don't know about any DV camcorders other than my Sony DCR-PC1. Under the "Digital Effects" menu is a "Slow Shutter" option. "1" is 1/15 second, "2" is 1/8, "3" is 1/4 and "4" is 1/2 second.

For all but the slowest of displays, setting "1" is adequate, though some tweaking of the monitor brightness and contrast is necessary to minimize the vertical bars (from some of the frame being scanned twice during that time. Some of the 1970s video games using vector graphics ("Asteroid" and "Descent"?) need setting "2".

The slow shutter speeds are also useful in poor illumination. Once I shot traditional Fijian dance by campfire light. 1/4 and 1/2 second added a sometimes surrealistic mood, sometimes enhancing fluidity, besides making it possible to get a good shot.

-- wally kramer (wally@steptech.com), July 25, 2002.


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