Fluorescent for greenscreen MKII

[Sjur Pollen]

Hi there everyone! (My first post).

 

I've searched the forums for answers on this but I haven't quite found the exact answers I was looking for.

 

I'm shooting a music video with a lot of green screen, and some bluescreen, but, at more or less no budget. Now I've seen some advice that reccomends standard industrial/household fluorescent as a cheap way to light a chroma-screen.

 

What I wonder is wich tubes to use.

 

I've found some green tubes with about 540-535 spectral peak ( http://www.prismaecat.lighting.philips.com...3_XUATLD_17.GIF ), and 4100 lumens output. I was thinking of using industrial 2-bank fixtures with white reflectors, cant seem to find any sensible 4-banks in my area (Norway).

 

Is this a good solution, or is it better to opt for 3500K tubes? (Then at least I can use the same tubes also for blue-screen.)

 

Also, what worries me is that since the spectral range is so narrow, am I risking a very low illuminance of the screen if the green paint (not rosco or anything fancy) is slightly different than the green light?

 

The biggest screen is about 5x3,5 meters (17x12 feet).

 

How many of these fixtures will i need to illuminate the screen properly? Will four do? Two in the ceiling, and two on the floor/sides.

 

I'll probably be shooting on the HVX200. Oh, and of course I will be using electronic ballasts...

Is there anything else I need to know about fluorescents for chroma keying?

 

Hope these questions are not to repetetive...

 

Any reply is greatly appreciated (except insults of course).

Edited July 4, 2006 by Sjur Pollen

[Guest will]

I'll probably be shooting on the HVX200. Oh, and of course I will be using electronic ballasts...

Is there anything else I need to know about fluorescents for chroma keying?

 

Flourescents are excellent for effects shots like this and you are correct in having some concerns.

Photometrics are a big problem with some of these fixtures, however I believe flicker is the worst

problem. I'm not sure what the policies are at stores in your country, but here in the states you

can purchase items and take them back if they don't work, or if you just aren't happy with them.

I suggest trying that and doing some tests with a HVX.

 

When the DVX100 came out we shot an entire interactive children's education DVD using all greenscreen

sets and industrial flourescents. Worked great, but we did plenty of testing before hand.

 

Also, make sure and get the $2 flouro bulb protectors. They are long plastic tubes which keep the

bulbs from exploding everywhere if you were to accidentaly drop one.

 

 

hope that helps

-will

producer, USA