Steve'sDigicams

video1 · Nov 28, 2005, 9:17 AM

Anyone knows why, or how to fix FLICKERING videos when shooting projected videos (images from videos projectors like on the cinema screen)
I have tried many cameras (Casio Z750, Z500, Z110, P5050, Canon A750 & Sanyo_VPC-C5) shooting on SD cards.
They all have the same problem :- Quality is OK except for the flickering.

Older video cameras using miniDV don't have this problem.
I suspect it is the frame/second, i.e 30fps that is too fast for the 24fps from the projected videos.
Could the storage medium (miniDV vs SD card vs DVD) be a factor?
I suspect shooting at 24fps will solve this problem. Help/Advice required.

Thanks

Dec 1, 2005, 5:42 PM

purchase a copy and be happy

airshowfan · Dec 5, 2005, 5:30 PM

First, let me just say that piracy is wrong!

That having been said, the flickering is caused by differences in frames per second being projected versus frames per second being recorded. The projector shows a frame for less than 1/30 of a second (or 1/25 or whatever the framerate is), then shows nothing (darkness) for a tiny bit of time while the next frame is loaded, then shows the next frame for a little while, then darkness for a little while... In other words, the 1/30th of a second (or whatever the framerate is) is made up mostly of showing a frame, but partly of darkness. If your recording device is "synchronized" with the projector (same framerate), you'll get the frame every time. If not, you'll get the frame most times, and the darkness a few times, per second.

The same thing happens when you're filming TV or computer monitors, which refresh so-many-times per second. Since the refreshing usually happens one horizontal row of pixels after another, starting at the top), screens shown on videos or on movies may appear to have horizontal lines or black rectangles moving up/down the screen, unless the framerate of the recording device matches that of the screen/monitor being shot.

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Nov 28, 2005, 9:17 AM	#1
video1 Junior Member Join Date: Nov 2005 Posts: 1	Anyone knows why, or how to fix FLICKERING videos when shooting projected videos (images from videos projectors like on the cinema screen) I have tried many cameras (Casio Z750, Z500, Z110, P5050, Canon A750 & Sanyo_VPC-C5) shooting on SD cards. They all have the same problem :- Quality is OK except for the flickering. Older video cameras using miniDV don't have this problem. I suspect it is the frame/second, i.e 30fps that is too fast for the 24fps from the projected videos. Could the storage medium (miniDV vs SD card vs DVD) be a factor? I suspect shooting at 24fps will solve this problem. Help/Advice required. Thanks

Dec 1, 2005, 5:42 PM	#2
bernabeu Guest Posts: n/a	purchase a copy and be happy

Dec 5, 2005, 5:30 PM	#3
airshowfan Senior Member Join Date: Dec 2005 Posts: 115	First, let me just say that piracy is wrong! That having been said, the flickering is caused by differences in frames per second being projected versus frames per second being recorded. The projector shows a frame for less than 1/30 of a second (or 1/25 or whatever the framerate is), then shows nothing (darkness) for a tiny bit of time while the next frame is loaded, then shows the next frame for a little while, then darkness for a little while... In other words, the 1/30th of a second (or whatever the framerate is) is made up mostly of showing a frame, but partly of darkness. If your recording device is "synchronized" with the projector (same framerate), you'll get the frame every time. If not, you'll get the frame most times, and the darkness a few times, per second. The same thing happens when you're filming TV or computer monitors, which refresh so-many-times per second. Since the refreshing usually happens one horizontal row of pixels after another, starting at the top), screens shown on videos or on movies may appear to have horizontal lines or black rectangles moving up/down the screen, unless the framerate of the recording device matches that of the screen/monitor being shot.