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Old February 2nd, 2007, 05:07 PM   #1
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Green Screen Lighting

Ok, I am doing a music video, the green screen will be 2 pieces of 10-12' x 9 1/2'. These are cut from photo drops and I'll be running clear small tape to keep them together(will this be good enough?)

Now onto lighting. I was gonna make my own 2 bank kinos as shown below to light the screen at about a 45 degree angle from the screen, both on each side. 2 questions

1. Is 45 degrees okay for a 2 bank?
2. Will 2- 2 banks be okay for that coverage?

4th question..... which bulbs would you recommend?

5th question(lol). At what distance do you recommend to prevent spill?

I'm done. Thanks for any input
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Old February 2nd, 2007, 05:56 PM   #2
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without knowing anything about the reflector design of your lights, it's hard to know how many you'll need to cover your drop evenly. It sounds like it'll be roughly 18x20... in which case 2 2-tube fixtures won't be enough. Generally, with kinos you flood it from the top and bottom of the screen, and build a raised floor in front to cover your floor fixtures. You could flood it all from the top, and save a lot of hassle, especially if it's less than 10' high. Flo's put out a lot of light along the lenght of the tube, but virtually none from the ends. So if you're thinking of placing them vertically, they certainly won't cover the top and bottom of your cyc. If you place them end to end, and entirely cover the top edge of your background, you'll have a far better chance of evenness. Back them off about 8 feet from the bg, and aim them towards the bottom, so the light falls off evenly. If you still need more brightness, add more fixtures - moving the lights closer will create hot-spots.

As for tubes, it depends on the distance of your subject from the screen itself. If you have a nice distance, and non-reflective floors, you can use less power by going with Kino's 523nm tubes. Otherwise, any 2800-3200K standard flo tube should work pretty well, specifically for the normally-avoided "green spike." If I were you, I'd start with the cheap tubes, and go from there.

Distance-wise (talent-backdrop), the more, the better. Most modern key software can deal with green-spill very well, but it's always best when you give it the cleanest background and edges possible. A hair light can add separation and help clean up green-spill in the hair, but it's not always natural looking.
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Old February 3rd, 2007, 10:13 AM   #3
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Quote:
Originally Posted by Jaron Berman
without knowing anything about the reflector design of your lights, it's hard to know how many you'll need to cover your drop evenly. It sounds like it'll be roughly 18x20... in which case 2 2-tube fixtures won't be enough. Generally, with kinos you flood it from the top and bottom of the screen, and build a raised floor in front to cover your floor fixtures. You could flood it all from the top, and save a lot of hassle, especially if it's less than 10' high. Flo's put out a lot of light along the lenght of the tube, but virtually none from the ends. So if you're thinking of placing them vertically, they certainly won't cover the top and bottom of your cyc. If you place them end to end, and entirely cover the top edge of your background, you'll have a far better chance of evenness. Back them off about 8 feet from the bg, and aim them towards the bottom, so the light falls off evenly. If you still need more brightness, add more fixtures - moving the lights closer will create hot-spots.

As for tubes, it depends on the distance of your subject from the screen itself. If you have a nice distance, and non-reflective floors, you can use less power by going with Kino's 523nm tubes. Otherwise, any 2800-3200K standard flo tube should work pretty well, specifically for the normally-avoided "green spike." If I were you, I'd start with the cheap tubes, and go from there.

Distance-wise (talent-backdrop), the more, the better. Most modern key software can deal with green-spill very well, but it's always best when you give it the cleanest background and edges possible. A hair light can add separation and help clean up green-spill in the hair, but it's not always natural looking.
Just curious, why would you use the warmer tubes on the screen instead of daylight. I've always felt daylight was better for greenscreen...
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Old February 3rd, 2007, 02:37 PM   #4
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If it spills on your talent, it'll bleed less than the bluer tube. That is assuming you're using tungsten lamps for the forground lighting. Yes, higher K tubes will look bluer on the screen, and perhaps help with the saturation... But either way, off the shelf flo tubes have basically no red spectrum and a huge green spike, so they should work great for greenscreen work.
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Old February 4th, 2007, 09:23 AM   #5
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Quote:
Originally Posted by Jaron Berman
If it spills on your talent, it'll bleed less than the bluer tube. That is assuming you're using tungsten lamps for the forground lighting. Yes, higher K tubes will look bluer on the screen, and perhaps help with the saturation... But either way, off the shelf flo tubes have basically no red spectrum and a huge green spike, so they should work great for greenscreen work.
Exactly! This is what I've found too. Greenscreen work is very forgiving as far as quality of fluorescents lighting it (lack of flicker is more important than CRI in this case) and its just important to get it lit evenly and with the color not spilling on anyone. I like to light with 3200K/3500K on the person/foreground and 5600K on the backdrop which works really well for making the person pop out from the screen.
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