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Old September 13th, 2009, 10:23 PM   #1
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Large TV in picture, use CTB?

Hello all,

I am getting prepared to shoot a scene involving two characters playing a video game on a large flat screen. For every shot I take in a new situation, I white balance the camera. That said, it appears that the tv display is quite bright and 'cool' in color.

I have two options that I know of. Buy large CTO sheets and cover the TV, then white balance and I can look at the TV directly and use it for a little light, or, use current CTB gels on some halogen work lights to 'match' the TV a little and I will have all the light I want, however slightly more 'lit up' then I wanted.

There may be another solution, I just don't know from here.

Any wisdom or thoughts are welcome.

Thanks,

Jer

Last edited by Jeremy Smith; September 14th, 2009 at 06:56 AM.
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Old September 13th, 2009, 11:32 PM   #2
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aren't "screens" in most shows done with green screen and overlay in post nowadays?
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Old September 14th, 2009, 12:14 AM   #3
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You'll get closer if you search for 2 stop ND <PLUS> CTO. Closer - but not perfect. TV pixels are very efficient light generators and put off a LOT of light. And the spectrum is NOT typically full color as you'd expect it in either the tungsten or 5600k world.

And buy a nice sharp Exacto knife and find someone with a steady hand to cut the gel EXACLY to the screen or a skoch larger. Even little ungelled screen slivers will glow distractingly.

The static of the screen surface should hold the gel in place.

That's an inexpensive place to start.

YMMV.
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Old September 14th, 2009, 12:30 AM   #4
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mmm...I've never seen ND used on a screen, you can achieve this via brightness and contrast controls.

Many modern panels have quite extensive control over color as well. It might be possible to adjust the screen warm enough to work with, although I doubt you could fully correct it this way.

Generally when we do playback, the footage has been color corrected to the appropriate temperature that, when played back on screen, will photograph properly under tungsten lighting. I did this myself once by outputting bars from FCP , setting up the camera pointed at a monitor displaying the output, then laid on a color correction filter and adjusted it live while watching the camera's output on a separate monitor. I tweaked until the photographed bars appeared normal.

Dave, I see about 50% live playback vs green-screen burn-ins these days. It often depends on whether the footage is available or cleared for use by the time we shoot. Playback has become much easier with the advent of LCD displays--CRT's used to require a special 24-frame playback setup and sync box on the camera, then dialing in sync and keeping an eye out for drift etc. LCD's don't present any issues for syncing without additional hardware so all is good.
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Old September 14th, 2009, 08:12 AM   #5
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Originally Posted by Charles Papert View Post
LCD's don't present any issues for syncing without additional hardware so all is good.
Assuming 1/60 shutter in 60Hz power land (ie. NTSC countries). Change to a shutter speed that isn't a factor of the power in hertz and you'll have scan issues, albeit not as badly as CRTs.
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Old September 14th, 2009, 11:42 AM   #6
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1/48th works fine also. You still have to be aware of your shutter speed/angle, but I have yet to encounter an unworkable situation with an LCD even while overcranking in a scene.
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Old September 14th, 2009, 12:44 PM   #7
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Thank you for the great thoughts!

Hello all,

Thank you for the great thoughts. Couple further thoughts in relation to some of the things said:

-I am looking for having the image on the screen itself and will actually zoom in on some video game characters, Pikachu and Bowser on the Wii (I do have permission) and will be going for that somewhat pixelated look. I'm trying to translate the idea of two guys that have spent WAY too long in front of the TV so the green screen effect might look too clean.
-There is a scene later where someone is watching a movie on a CRT monitor and frankly, I'll either try the green screen or just have them watching with some audio, the video out of the frame...that usually drives me crazy though, it 'feels' unfinished to me as a viewer.

-The ND filter idea was one that I had not thought of, but as also mentioned, I do have control over brightness etc. I have yet to fool with the color to see if the image temp will match or not, but I can play with that with the CTB gels on the lights I have too. I am not opposed to getting some larger CTO gels, hence this post, but if I can create something with what I have, I'll probably stick to it that way.

-The screen flicker I have not noticed and I am at 1/48th, thanks for the reminder though Shuan. Oddly enough, what sticks out, are the Wii's sensor remote IR signals, two little eyes of blue light sitting on top of the TV. I'll have to move that.

Thanks again to you all, I believe I will have to experiment at this point with all this info and make a decision. Its nice to have an informed one.

Jer
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Old September 14th, 2009, 12:59 PM   #8
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1/48th works fine also.
Thanks Charles. I'm used to INCREASING shutter speed past 1/60 to force open the aperture so I'm always cognizant of shutter speed/display rate issues.
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Old September 14th, 2009, 01:22 PM   #9
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Originally Posted by Charles Papert View Post
mmm...I've never seen ND used on a screen, you can achieve this via brightness and contrast controls.
Charles,

I suspect I might be a generation or so older than you and that habit came from working with a lot of CRT Tv sets over my career where you were lucky if you HAD brightness and contrast controls that were accessible to the end user. If so, they were round analog pots, not menu driven digital adjustments.

I agree that the advent of LCD TVs have made shooting screens a whole lot easier - if just for the fact that we don't have to mess around trying to find a sync refresh rate on the camera that matches the monitor without leaving a visible black line somewhere.

Still, the "old school" way I described has the dual advantages of being fast and cheap - plus you don't have to try and re-create the original expected settings after the shoot to get that school, factory, or living room TV back to where the owner expected it to be.

I also found it beneficial when I wanted the presence of a TV in a dimly lit scene. Dialing the brightness on a CRT TV tube down to the point where a sensitive camera can balance it with a dark scene, can "sometimes" be problematic - again and especially when you're dealing with a "classic" tube TV.

But as always - YMMV.
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Old September 14th, 2009, 04:57 PM   #10
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If you have to resort to gelling the face of the TV - I'd say bring a can of dulling spray, some blue masking tape & newspaper. You may find the gel needs dulling after it's applied to the TV. (Dark areas may have heavy reflections, and you may not get every last ripple out of the gel).

Though my guess is you'll have all the controls you need right on the TV remote - which means you can tweak as you look through your VF, too. Good luck!
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Old September 15th, 2009, 01:06 AM   #11
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If you have to resort to gelling the face of the TV - I'd say bring a can of dulling spray, some blue masking tape & newspaper. You may find the gel needs dulling after it's applied to the TV. (Dark areas may have heavy reflections, and you may not get every last ripple out of the gel).

Though my guess is you'll have all the controls you need right on the TV remote - which means you can tweak as you look through your VF, too. Good luck!

Well, yeah, you COULD use dulling spray I guess.

But silly me... on those occasions I had reflections off the gel OR the glass - I'd just rotate the set a few degrees until the reflections were gone. How "old school" of me!

WORST case scenario you'd angle the set at 20 degrees and hang DUV from a C-stand arm to block reflections.

And as to looking through the VF, IMO, that's kinda what the modern LCD directors monitor is for isn't it?. Have the crew run a BNC feed to a 7" handhold-able LCD and you can futz with the screen all you like while seeing EXACTLY what the camera op sees without having to run around?

What's really fun is having the best of BOTH worlds at hand. Traditional techniques when they work best in a given situation - modern options when the old style just won't do.

; )





Sheesh.
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