Lowel V or Tota for Green Screen?
 

Looking for suggestions on lighting a greenscreen with either 2 totas or 2 Lowel V lights, anyone have any experience-suggestions? It appears that the Tota will give a better broad light source.


My green Screen is currently only 8 feet wide (roll of Savage Seamless paper) perhaps i only need one light to light it if stragically placed?

So long as you can evenly spread the beam, either one will probably work just as well. You can use umbrellas to spread the beam out, or softbox. The harsher direct light from either will bring out some flaws in your background (wrinkles/creases). The only way around that would be frontal lighting...but then it will be in your shot.
I don't recommend using one light, falloff would cause exposure issues, and that is the deal-breaker for quality keying.

What Oren said. You need very even broad source lights, if it's a full length shot probably 4 umbrellas or soft boxes, if a medium shot two would do. Even, soft light is what you need for green screen or the screen texture, flaws, light fall-off etc will give you keying problems. Direct light from a harsh instrument like a tota would be way bad in my experience.../ Battle Vaughan

I use direct open face lights for green screen all the time. It's just a typical studio wall, no problems. Two Lowel Totas work great, but you need to use some black wrap to keep the light off the talent. I put the lights probably about 8' from the wall, at about 45 degree angles and adjust till I'm within 1/4 stop even all the way across. Talent is positioned probably 10-12 feet from the wall. V-lights should work about as well but they only go up to 500 watt lamps, I think. That's usually OK if you don't overlight your subject. I like to keep the green screen about half a stop to a full stop hotter than the key on the subject, although sometimes I 've done it a stop lower than the subject...seems to work better if it's a little hotter.

The primary difference is that the V-light maxes out with a 500w lamp.
The Tota will allow up to a 750w.
So the Tota will allow you to move the fixture somewhat farther away from the wall to even out the spread and at the same illumination value.

That said, one big downside of tungsten for green screen work is turning a large part of your power draw into heat rather than light. In a small room, high wattage tungsten floods make for hot talent and pretty miserable shooting conditions.

And putting a Tota in a softbox simply gets you less light at the same power draw and heat.

That's why of all the choices, I think fluorescent is a much better call for modern green screen work.

The big key to good greenscreening, however is always going to be UNIFORMITY of the key surface. And that's NOT achieved with simply getting the light devices right - it's about ALL the keying components working together. So the light source is ONE element. The green surface is another. (Light diffusing "nappy" fabric will diffuse reflections more evenly than say a hard painted wall) And finally, the distance and geometry of the space being used will also have a big effect on the quality of the key you can pull.

So keying isn't just about one leg of the triangle. It's about balancing the whole structure. Soft light. Good key surface prep. And proper shot geometry with the talent separated far enough from the key surface to avoid excessive reflected spill from the key to the subject.

Get ANY ONE of those wrong. And your key gets harder to pull. Simple as that.

YMMV.

My green screen lighting is a result of trial and error. but this is the set up I have arrived at. 2 totas with black wrap and diffusion. But I haven't tried the 1/2 to a full stop hotter on the green screen. I will give it a try the next time. I control the level with dimmers and I have always gone for the 1 stop lower setting. I was always trying to keep green from reflecting back on the talent and giving a soft edge on the chroma key. I use the Zebras on the camera to try to get even illumination across the green screen back ground. It sure makes it easy to see hot spots.

I would suggest using flo lights for any green screen. They're perfect for the job, cheap (try Coolights or Amvona), energy efficient and don't generate a lot of heat. Plus, you won't need many - probably just two, although I've used one, centered near floor level and gotten acceptable results. With hot lights you could easily overlight the green screen, resulting in spill and keying problems.