Professional Green Screen Lighting

[Midicon]

In my experiences i shoot 1 to 1 1/2 stops under the subject to prevent spill and keep a good contrast between the foreground and the background… Keylight is pretty powerfull it can pull out most stuff pretty easy i have tried shooting with a little over and i got more of a washed out green and the light might spill on you subject.. its a balancing act the best way is to experiment because ther is no set that works flawlessly…

[Chris Smith]

You can light the screen at generally the same stop as your main subject. The idea is that when you sample in the film transfer, and get info on that greenscreen whithin AE, it should be as close to pure green as possible ideally (0,255,0).

But even if it’s a stop or two off, you can still usually get a decent key.

But the closer you get to pure electronic green, the more latitude there is to get a key from.

Chris Smith
https://www.sugarfilmproduction.com

[Phil Chang]

“Normally I light the green screen a stop under my taking stop. For example, if I have a T2.8 on the camera, I would light the green screen at a T2. ”

This is giving the background a stop more light than your subject. I would keep it the same or slightly less. If you get 2.8 on the subject, keep the background at 2.8 or -1/2 stop less. Keep the subject as far away from the background as possible to keep light from the subject spilling on the background and light from the background reflecting back on the subject. Even then, if you are giving the background more light than the subject there is a tendency for the light to wrap around the subject (you will see a color fringe from the background on the subject). THAT is from the light off the background flaring within your lens.

Even if everything is perfect, something will happen… it alway does! AE’s keylight is awesome though!

Phil

[Steve Roberts]

Hmm … if he’s exposing at T2.8, and his meter reads T2 at the background, then he is underexposing it. Yes?

Steve

[Chris Smith]

[Steve Roberts] “Hmm … if he’s exposing at T2.8, and his meter reads T2 at the background, then he is underexposing it. Yes?”

That is correct. If his background is a 2.0 on his meter than the meter is saying that you would need to open the lens a stop to be able to expose that correctly.

If his subject is a 2.8 and his bg is a 2.0 then bg is a stop darker indeed.

Just like if you walked that meter in the sun and got a f64 it doesn’t make the outside almost black, but obviously bright as all get out.

Chris Smith
https://www.sugarfilmproduction.com

[Chris Smith]

side note, I couldn’t agree more with Phil about distance from the Greenscreen. The last thing I shot GS a month ago, my subject was 15 ft away. I also put my cam another 15 from the subject and shot on a long lens. I also use a touch of slightly warmed up rim light on the subject to help the edges.

Chris Smith
https://www.sugarfilmproduction.com

[Phil Chang]

Right you are… my mistake. Sorry about the confusion.

[Midicon]

chris
what were you keying?? and how did it turn out did you still get spill… i would imagine that it turned out pretty good… i keep my subjects a good distance but i have never shot from that distance you must have had a huge GS

[Chris Smith]

I was shooting an element of a girl on GS for an agency as an element in a cell phone ad. We lit her frontal with two bare kino tubes and did vertical kinos on either side as backlight. We used sky pans on a 12×12 GS. Didn’t use much of the GS since as mentioned we shot it on a long lens (around 180mm if I remember correctly).

Don’t know if it turned out well because after I turn in the dailies I walk from the project. Don’t know what they keyed it with or how it turned out.

Chris Smith
https://www.sugarfilmproduction.com