Lights for bluescreen-shot

[thomase]

Ok, now that my exams are finally behinfd me I got some more time to create some footage. I wanted to do some bluescreen stuff but to be honest I don't have any clue about lighting...
I know there's the "classic three point" setup but I don't even know what this exactly is?

Can anybody help (draw a diagram maybe)?

Thx

[kvisuals]

just take care about the shadows....
make shure that there is now shadow at all.

I have a setup with lights on the blue screen, a light above my object or person lights from the right, the left and of course from front as well. I hope that helps a bit.

sorry no drawing at the moment and no time to do that....have a gig tonight and need to prepare some stuff. :-)

cheers

[cat]

3 point lighting is
Key light, your main light, creates shadow on your subject, 15-20 degrees one side of the camera
Fill 15-20 degrees the other side of the camera, to fill in the shadows a little, cameras have less dynamic range than the eye
Rim to seperate the subject from the background, basically above and behind the subject to create a halo, a little yellow will tame ny blue spill from the screen

Lighting the screen is also important, no shadow from the subject should fall on it and the illumination should be as even as you can make it, try and minimise hotspots

[devonmiles]

recently I used plain blue video on a 2x3 meters rear projection screen as background, 2x par 100 on tripods at 20 degree on the right side of the camera and a softbox on the other side.
I cant provide a bomb prove advise, so just play around with positions, move the lights up and down till you think the result will satisfy you.

[holly]

Yeah, experiment. No key is ever perfect, you just need it to be "good enough". Get daylight balanced bulbs. Incandescent light is very yellow which kills the blue of the screen.
:yep:

[deepvisual]

hmmm.
rumour has it that green is better blue for shooting on dv.
you need to light the screen evenly with two lights
and use another two or three for the subject- you will need some shadow on your subject to create modelling so set one front light on full and the other about 30% or use a reflector instead... set your front lights around 30? from straight ahead and 60? from eye level . use a diffuser if you can or better still a softbank. if you can get a light meter, keep the levels the same on foreground and background, then you can't fail

[Syntax]

what kind of lights do you (experienced keyers) recommend for lighting the screen?

[stickyhead]

im trying out green screens at the moment, check this site out


http://www.computerarts.co.uk/tutorials/3d__and__animation/bluescreen_on_a_budget

its helped me no end

[seex]

what kind of lights do you (experienced keyers) recommend for lighting the screen?

as Holly sugested, use daylight bulbs, and i think softboxes and difusors have also been recomended.

[videoteque]

Daylights are either HMI (ultra expensive) or fluorescents. Most green/blue studios I have seen (in picture!) use fluos to illuminate the green/blue backs. It generates less heat, use less electricity, etc.

[stickyhead]

has anyone got any green screen material off the net or anywhere in the uk??? i have been looking but can't find any where i can buy this kinda gear from

[holly]

I had my bluescreen made by Rosebrand (http://www.rosebrand.com/A_Com/showprod.cfm?&DID=6&CATID=5&ObjectGroup_ID=34). They give quotes over the phone.

For lighting I use 8'ft flourescent fixtures I scavanged from an abandoned dept store. Over the years the ballast has gone on some of them, so I have replaced the ballast (it's the power/pulse regulater available at every hardware store) and eventually because this was a pain I have bought some new fixtures at a local business wearhouse supply for about $80. I re-wired the ones that hold 4 bulbs to be 2x2 and dim each channel seperately.

:eek: WHAT? You aren't supposed to dim regular flourescent fixtures! This will damage them.

:rolleyes: oh, bullshit. for under $100 I can get NEW regular 8ft flourescent fixtures which may or may not burn out in 5 years because I put them on dimmers.... Compare that to "professional" dimming flourescents that cost $3500+!

I also got one of these:
http://www.americandj.com/images/new/Stage-Setter-8.jpg
and two of these (maybe not this brand):
http://www.americandj.com/images/new/DP-DMX-20L.jpg http://www.americandj.com/images/new/DP-DMX-20L.jpg
to control all the lights from one location near the camera. It is DMX and MIDI capable so there are future staging possibilities....

[eisenstein]

i'd like to second the use of flourecents in lighting a greenscreen on a budget. we do live keying in a small space using a v4 to pull the key. we went through professional fresnel lights, cheap home depot halogen worklights, and finally decided to go with 4' banks of cool blue flourescents. the keys are cleaner, the setup is easier, the heat is waaaaay lower. if you're on a budget, this is the way to go.

oh and use professional chroma paint- its not much more money than a regular gallon of green matte paint and the quality is instantly noticeable. full writeup and pics:

http://www.theavclub.tv/greenscreens.php

[videobrian]

to quote one source about budget bluescreen lighting:


An old favorite of pros and amateurs alike is a single thermonuclear fusion source, placed 93 million miles away. This light source gives perfect corner to corner illumination and makes a perfect match between the key level and backing level. Shadows are easy as it makes only one set of shadows. If you place a water vapor diffusion screen several thousand feet up, you get a great shadowless light. A thinner water vapor diffusion softens the shadows nicely. Those who are inexperienced at controlling these types of diffusion may want to use a large silk or other diffusion instead.
I'm serious--I've done some great mattes this way. If you're shooting spacecraft models, this can be the best method. Plus the rental charge can't be beat. The Death Star trench scene in Star Wars used this very same light source.