View Full Version : green screens

12-17-2003, 04:30 PM
any advice on setting up a green screen. We've tried it and are getting OK results. Nothing I'd like to put out to tape.
Can someone help?

12-18-2003, 04:28 AM
Green screen?, on a set, or in a 3d project?

On set this is something you'd have to discuss with a cinematographer...
In 3d...why? you've got alpha's (unless you're doing post on some analog edit set)

12-18-2003, 10:58 PM
In brief, Make sure the background is evenly lit.
Make sure and separate the talent from the background so there is no color bleed on the talent.
Give plenty of backlight to your subject for better separation.
Possibly add a slight peach or warm color gel on the backlight.

If possible, use SDI or Component feed. Composite or DV isn't the best for Chromakey.

If still not happy, there are plenty of key programs available. I recently heard that Ultra Key works pretty good even with composite or DV.

There is a lot more to learn, but without knowing more about what you are specifically trying to do, this is a good start.
I wish you luck.

12-19-2003, 08:58 AM
Ted's advice (above) is very good.

I'd just add that throwing some light on the green screen is good, but avoid any "spots" of light that may make the greenscreen look white on video. You want a bright and saturated green.

As Ted said, mini-DV and DV-CAM are not very suitable if you want professional looking results. It's hard to get a good looking key due to the high compression rates of these formats. DVC-Pro50 and Digital Betacam are better.

Professional keying applications like Primatte and Ultimatte are worthwhile.

12-22-2003, 05:26 PM
Hi There

shoot on digi beta. Also keep any reflective matierial down to a minimum and if you can have a make up artist on hand to stop those shiny bits on your actors as it's all too easy to pick up even little bits of green in reflective area's. If you can use a cameraman familiar with green screen. It'll save you a lot of grief later.
Discreets combustion has a really good keyer and tool set for this kind of work. Also if this is something you intend to do a lot of in the future then check out reflectmedia.com they have a BBC developed chromakey system that uses a super reflective backdrop and a ring of Blue/ Green or red LED lights that sit round the camera lens. It enables you to set up a "green screen" in minutes without a complex lighting set up. and if memory serves me right you can get good results even on DV Check it out.