Filming off of a TV or LCD

[Susie Sahara]

Hello,
I'm new to this forum (or any forum, really) and I have what I hope is not a redundant question. Has anyone tried filming off of a TV screen or a projection screen (from a laptop hooked to an LCD projector). I don't want a lot of lines for this film. I mean, I'm not filming credit sequences (though I may in the future) -- I just don't want it to have tons of roll bars or whatever you call them. for the record I am using a Canon 814 E and using Kodachrome. Can anyone give me some good advice?

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[MovieStuff]

Actually, shooting off the Laptop screen would be better than shooting off the LCD projector screen, I think. The color will probably be truer off the laptop.

- However -

If you have access to a non-linear edit system and your movie camera can shoot at, say, 6 fps, there is a better way to copy the video to film:

Place your video clip on the time line of your NLE system and set the "speed" adjustment for 25%. This will quadrupal the length of your clip by adding an extra three frames of each video frame. In the end, your video clip will be playing four times slower.

Now, set up your video camera so that it is shooting off a regular high quality video monitor (not an LCD monitor or laptop). The CRTs (picture tubes) of regular video monitors have MUCH better resolution than LCD panels. However, because the CRTs don't use an active matrix like LCD panels, you can get the "roll bar" you spoke of when shooting at 24fps off the screen.

However, if you shoot at only 6fps, the scan rate of the CRT is WAY too fast to be seen by the slower shutter speed of the movie camera. And, since the clip you are copying is ALSO playing back at 25% speed, everything evens out when the film is played back at normal speed after processing!

Also, you will get a much better exposure at 6fps which will make shooting K40 much easier to do.

NOTE: Use a fairly long (telephoto) lens on the movie camera to minmize the curvature of the TV screen you're copying off of. And, of course, the room lights off totally.

Hope this helps!

Roger

[Alex]

Susie, the key to avoiding the roll bars on a screen is to lower the shutter speed to below 1/30th of a second.

Unfortunately, that requires slowing your camera down from the "normal" 24 frames per second.

I believe the canon 1014xls has a 220 shutter that may allow you to shoot a 18 frames a second and severly miminimize the roll bar.

I don't think your camera has the 220 degree shutter capacity.

The simplest approach for you is the using the right camera, (the canon 1014xls at 220 degree shutter), and shoot your entire movie at 18 frames per second.

Any other camera with a 220 degree shutter and 18 frames per second should also work.




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Alex

[mattias]

alex, have you actually tried this? my experience is that you need to go as low as 9 fps to get satisfactory results, even with a 220 degree shutter. having a 1/30 shutter speed eliminates the *black* roll bar, but the image will still be rolling and flickering unless you're using crystal.

/matt

[MovieStuff]

Back in the 70's I used to shoot with my Sankyo XL sound movie camera off of TV at 18fps on Ektachrome 160 all the time. The Sankyo had a 220 shutter and it definately helped a lot, but there was still a noticable roll bar. Going to 6 frames per second seems to be the trick as Interformat does some transfers to film from video and they, too, use 6 frames per second to rid the film of any roll bar (according to a recent discussion with Michael Hinton). Of course, the getting rid of the roll bar is the easy part. Making the images playback at the right speed is the trick! That's why I suggested slowing down the image using a NLE system, which I realize now is not an option for Ms. Sahara.

Roger

[Susie Sahara]

Thank you Roger, Alex and Mattias for your answers. I guess I need to get a camera that shoots at 9 fps or work something else out with the scene. Hmmm...

I really don't want to shoot DV as I've had some bad experiences with it. Not that I don't like the way it looks but the last time I tried to film the stupid cameraman dropped it on the ground and my school tried to make me pay for it's repair!

Well, anyway, I'm going to re-write my scene I think.

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[Alex]

18 fps is not perfect, it will not completely get rid of the roll bars. 9fps per second is the ideal speed.

However, if you are going to show the movie in real time (18fps) on Super-8, and you cannot do it the way Roger suggested, 18fps with a 220 degree shutter is the best compromise.

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Alex

[Susie Sahara]

Thanks Moveistuff but I don't have access to NLE system.
This is for a school project and I wanted to show my actor going insane over some miscellaneous images. Do I have to adjust the monitor, shoot in slow motion, etc?

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