Lighting/greenscreen For Feature!!

Bluewave07

Bluewave07

Active member
Hey everyone,
I'm starting a new feature in a couple of weeks which will be shot primarily outside at night as well as on a greenscreen.

My first question is lighting. What sort of lighting is available (preferably as cheap as possible!) that is useful both for lighting a greenscreen and lighting very dark exterior environments. Once again, tight budget so cheap is good.

Also, what settings are best for greenscreen work and exterior work? I've heard some stuff about adjusting the detail level and master ped, but what exactly are the numbers??

And finally, a more random question, what sort of fabric is recommended for building a greenscreen (buying from Joanne, so if anyone can remmeber the name that would be excellent)

Thanks a lot!!!
 
work lights baby!

i got a set of 2x500 watt for 1000 watts on each stand,
2 500's and 2 500's for a night scene, gives you around 2000 watts of power to play with, of course they are only 500's so they cant be THAT THAT far from the subject.
 
if using work lights you'll want to bounce them off some foam core boards or through some diffusion material to evenly light and take out the hard edges. Put you subject as far away from the green screen as possible and light him separate. Good luck it's tough with SD.
 
im not sure of the names of the programs, but ive seen some Excellent keying done on SD footage.
 
I'm shooting green screen with the HVX. Never had much luck with miniDV because of the compression. I painted a wall green rather than using a cloth backdrop.

The green screen needs to be evenly lit with soft lights, and it needs to be lit independently of the actors. So, at a minimum, you need two lights to light the green screen and then between two and three lights to light the actors.

The backdrop needs to be very evenly lit, but not too bright. If its over-lit then color from the background will spill back onto the actors making keying difficult. Its much easier to key if there is not only a color difference, but also a luma difference between the foreground and background. I'm using photoflood lights for this purpose. I got a set of three lights without bulbs from a camera supply store for about $150. Then I use 100 watt daylight adjusted consumer bulbs (lke 'Reveal' bulbs) rather than expensive photo flood bulbs. Two of these placed at about 5' high, and about 12' back from the backdrop, as far to the sides as I can get them so that the light from them doesn't hit the actors.

Then I use two more lights between 3' and 5' from the actors, just to light them. And sometimes I stick a small light in the back corner to backlight the actors, to try to create a sharper edge around them and counteract any spill from the background.

Advice:
#1) Light the background first, and adjust the lights so that they are equal distance, and then adjust them to minimize overlap on the background so that its very evenly lit. I use the camera's autoiris, pointing at different parts of the backdrop, to check the brightness for consistency. I don't trust my eyes to do it.

#2) Turn off the background lights and light the actors. Set the white balance with the actor holding a white card, and the exposure with the background lights turned off. Then turn the exposure to manual to keep it from changing, then turn the background lights on again. You might need to adjust the exposure a bit after that.

#3) When you are lighting, its important to avoid getting shadows from the actors on the background, or it will make keying tough.

#4) Work lights and other really bright lights that you might use to illuminate an outdoor night scene really don't work well with green screens. I tried to use work lights for this purpose. If I illuminated the background with them, I couldn't get the light even enough, there were always spots that were blown out. And I couldn't keep the reflected light off the actors. I tried bouncing with foam core and couldn't get the directional control necessary or even brightness. To avoid getting a shadow of the worklight I had to put the light angled up at the foam core, and the foam core angled at the screen. Result: the light bouncing off one end of the foam core was a lot brighter than light from the other end -- causing the backdrop to be unevenly lit. I tried using them to light the actors, and couldn't keep the shadows and light from them off the background.

Outside lighting at night is tricky. Its all about the distance involved and the fact that the brightness of the lights varies radically depending on the distance between the light and what its illuminating. Framing closer shots and moving the lights closer is one way to keep the costs down. If you have to shoot a really wide shot and if it needs to be fully illuminated then you need a lot of high-powered lights.

So... photoflood lights *may* be useful for lighting tightly framed shots at night outside. My experience is that work lights and really bright lights are mainly useful outside and won't have much value with a green screen.
 
Settings: Turn the detail level down a bit, maybe -3, so the edges won't be over-sharp which might cause artifacts. Also, you might want to use a Cinelike gamma to reduce video noise.

Search for chromakey or greenscreen on DVXUser. A lot's been written about it. I learned a lot from Jim Arthurs' posts.
 
Andy and PaPa,
Thanks so much for your input! This really helped; I know keying is difficult w/ SD but we're gonna try the best we can. Thanks a lot!
 
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