Designwerks – Need Advise with Studio Lighting for Green Screen Cyc wall

[Mark Suszko]

Until the experts chime in, you have me:-) I think you get more coverage, for less money, by DIY’ing banks of long fluorescent tubes in highly reflective troughs. The fixtures are dirt cheap. Later, when there’s budget, you can put real KINO or similar brand tubes in, and better ballasts, if needed. Since what you need is soft, shadowless light with a lot of coverage, a strip of PAR bulbs with diffusion in front of them would also do the job, though they would make more heat and draw more energy than the tube lights. LED lights are arrays of individual POINT sources, so unless they have a diffuser in front, what you get is an imperfect attempt at “soft” light with as many individual shadows as there are LED’s in the array.

[Bill Davis]

Green Screen is a SYSTEM thing. Never just about one thing.

One part is the greenscreen surface itself (you’re fine with that.)

Another part is the lighting – and to my eye, you’re actually not very far off with that – depending on a couple of things. First, how big are the typical subjects you want to shoot? If it’s a guy at a desk, you’ve already got plenty of lighting in place to do that. Now if you want to key out a group shot of a choir and key them well, then no, you do NOT have enough light.

One part is the CAMERA you’re using to shoot your footage. How it generate, recordes and plays back the video signal has a BIG impact on how things key. So what are you shooting with?

Another part is the KEYING software you use. Again, more modern softwware is more tolerant of lighting issues.

I did this key shot with a single 2 lamp kino type fixture. I can’t get to the original right now to show you how bad the lighting was, but the shadows and the inconsistency of the greenscreen would have made you cringe. But with a garbage matte and keying in FCP-X, they came out perfectly usable for web video. And I was using 4:1:1 DSLR h-264 footage no less!

The point is that keying is about balance. Size of the subject, amount of light, keeping the key light on the key surface and lighting your subject separately. It’s actually WORSE to over light a key screen so that you have so much green light flying around that it infects everything. You want enough green to provide a background for the active scene, and no more.

One small issue is the stage depth I’m seeing here. You’ve got a LOT of green up the back wall, but not much separation depth front to back. Green is going to be spilling from any lighting you put on all the vertical distance on the GS and bouncing all over heck and back. You MIGHT be better off putting in lighting you can turn on for the AREAS you want to use as backgrounds, rather than just lighting up the whole GS for everything.

Actually, unless the camera you took those shots with is doing something squirlly with reading the light falling on the walls there are large areas that look like they’l pull a key just fine.

So don’t over think this. Get some subjects in there. Get YOUR camera and software working – and see what you can get. If you have one of the newer monitors that do a false color exposure overlay, that’s really useful for setting keys. (Much easier to adjust than a WFM!)

You might be closer than you think already and just not know it!

FWIW.

Know someone who teaches video editing in elementary school, high school or college? Tell them to check out http://www.StartEditingNow.com – video editing curriculum complete with licensed practice content.

[Shaun Lupton]

Thanks both of you for the advise. We currently shoot with DSLR Mark 2 cameras. We will be in the near future shooting with the new 4k Blackmagic video camera. We are just getting way too many hotspots with our leds. It feels like some areas are over exposed and some are not and I have a bunch of leds on the grid currently but I feel like I need another complete set to just get even lighting. That is why I was thinking of going with space lights for green screen to get even lighting and then taking down some of the leds from the grid and use those to light the talent. Im trying to figure this all out without having to pay a fortune for kino lights as that is just not in my budget at the moment, but something that will light the cyc eventually. In the mean time im trying to find the best way to evenenly light the cyc as are plan is to also rent it to other videographers so it has to work universally with all video cameras etc. Thanks you both for the advise as both are well taken in finding the right solution.

Shaun

[Todd Terry]

Well SpaceLites are great for big blue or greenscreen stages where you want nice even lighting of the cyc, and a nice even high level of all-over ambient lighting from the same instruments.

That might not be what you always want, though. In fact, it’s almost never what I want when shooting greenscreen on stage here. I try to light just the screen and nothing else, with as little spill as possible and no ambient lighting coming from those instruments…. and then light talent completely independently from that.

Mark’s advice is right on the money… there’s no cheaper or easier solution that hitting up a home improvement store (Lowe’s or Home Depot) and stocking up on plain ‘ol shop lights, either two-bank or four banks. You can get a two-bank fixture for literally 15 bucks. We have several of them that I bought years ago when I needed something quick and cheap, and still use them today. Yes, you can use real Kino tubes later on, if you plan to also ever use them to light talent. I wouldn’t do that though… while they are great for cycs they aren’t controllable enough really for much other use… ergo it’s a total waste to put better tubes in them. Just use the off-the-shelf flo tubes from the same store (available in more-or-less tungsten or daylight balanced). Since you are only using them to light the greenscreen, it doesn’t matter one whit that their CRI isn’t too high… they work just fine.

We painted ours black so they didn’t look TOO much like a DIY project… they really do work great for this purpose and couldn’t be cheaper.

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com

[Rick Wise]

All great posts. I was originally contacted directly about this problem and urged Shaun to post on Cow. I’m sure he’s glad he did!

I really have litttle to add other than to agree totally with the use of shop fluorescents for the green screen, and paint them black to make them look professional. Oh, also, get the talent as far away from the screen as possible, which in your case is not very far. Some green light will probably bounce back and give green edges to your talent and props. Since you cannot use distance to your advantage, try light, diffused back lights with a slight warming gel such as 1/4 CTO to counter any green contamination. The intensity should be just enough to neutralize the green spill and not so hot as to make a hot edge, which will not key correctly.

Rick Wise
Cinematographer
San Francisco Bay Area
https://www.RickWiseDP.com

[Mark Suszko]

CTO or straw or bastard amber gels are the counter for blue screen. Magenta gels counter spill for green screen.

[Rick Wise]

True, Mark, though I’ve found the 1/4 CTO works pretty well to control the green. But you’re right, magenta is better.

Rick Wise
Cinematographer
San Francisco Bay Area
https://www.RickWiseDP.com

[Mark Suszko]

In your defense, Rick, amber light spilling off hair and shoulders looks better and more natural than magenta would:-) But ideally, the talent is lit completely separate from the green, and there’s enough separation to avoid the spill altogether.

[Todd Terry]

I also always caution people not to light the screen more than is needed. I don’t mean intensity, I mean area.

A bigass multi-sided cyc doesn’t need solid lighting everywhere if you’re just shooting a locked-down 80mm talking head shot… in that case just light the screen area that’s in frame. Otherwise you’re just wasting time and energy creating potential greenspill and reflections, especially in a wraparound stage environment.

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com

[Todd Terry]

I meant to mention that when I do greenscreen, if I am daylight lighting (which is the case about half the time), I’ll often use an uncorrected tungsten instrument as a backlight. I tend to like the look when the backlight is a little warm, and that combo is pretty pleasing.

I do that purely for aesthetics, not to help the key. If you are using decent keying (say, KeyLight or Ultimatte, etc.), I’ve found mattes are clean enough if you light both the screen and talent well so that I generally don’t have to worry about battling spills.

I almost always without fail shoot for my own projects… but recently I was a “hired gun” for another director who came in from NY to do a greenscreen shoot here. The talent was a late-middle-aged guy with fairly greyish-white hair. It was an all-tungsten setup… and the director asked me to put some quarter CTB on the backlight. I’d never put blue on a backlight in that situation before, but he said it was a look he liked. We tried it, and yeah, it did look pretty good (and the matte was clean as a whistle).

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com