Taping a projector slide presentation -- color shift :?:

[shieber]

I need to video tape some projector slide presentations. When I tape the slides shown on the screen, the VTR continously shifts the color from an overall reddish tint to bluish tint and then back again. IT's as if the VTR is trying to make an automatic adjsutment for something and can't stop. But I can't figure out what autoadjustment to turn off. Setting white balance to fixed doesn't help. The VTR works fine except wihen taping slides projected on a screen.

I've tired several diff VTR s and the results are the same.

Any thoughts?


tia

[zoobie]

"why doesn't my car run?"
you'll need a lot more info in your post to get an answer...be very specific with your equipment and technique

[gadgetguy]

You'd be better off scanning the slides and recreating the slide show in editing software.

[2Bdecided]

"projected" as in 35mm transparencies, or "projected" as in MS power point, PC, VGA-type projector?

If the latter, I bet it's the colour wheel (DLP-based tech?) - the RGB colours on screen are alternating thousands of times per second - too fast for the human eye to detect it, but such that a fixed speed shutter in a camera can catch slightly more of one colour than another, leading to perceived colour shift.

A longer shutter speed might help in this case. A direct screen grab, directly inserted into the video later, would be better.

Cheers,
David.

[shieber]

This makes snese since it happens with diff brands of cameras when taping digitial projectors (power point and such) and some do it worse than others and shift at diff speeds. If I had the the slides on didsk and didn't have to tape them, that would certainly be preferable but not always an option. So I'was hoping to conquer the color shift prob.

I'll see what I can do about shutter speed and meanwhile, any other suggestions welcome.

thanks,
sh

"projected" as in 35mm transparencies, or "projected" as in MS power point, PC, VGA-type projector?

If the latter, I bet it's the colour wheel (DLP-based tech?) - the RGB colours on screen are alternating thousands of times per second - too fast for the human eye to detect it, but such that a fixed speed shutter in a camera can catch slightly more of one colour than another, leading to perceived colour shift.

A longer shutter speed might help in this case. A direct screen grab, directly inserted into the video later, would be better.

Cheers,
David.

[jagabo]

Since these are slides, just find one frame where the colors are right and stretch that to the desired duration.

[shieber]

Thanks.
sh