When you are using chroma or a green screen it is possible to create cool visual effects, but it is just as easy to screw up a chroma shoot which will take lot of time to fix it in a post production. I love using my green screen for visual effects. If used properly, it allows for a vast number of cool effects to be created with relative ease.
In this tutorial we will cover five mistake that you should avoid while shooting chroma / green screen footage.
There are 7 common green screen mistakes that most people run into:
- Avoid grabbing colors similar to green screen
- Not matching the perspective
- Shadows on the green screen
- Unevenly lit green screen
- Motion blur in front of the green screen
- Clipping out of the green screen
- No backlight
As we can see the person in above image is casting a very dark shadow onto the green screen which will give you lot of problems when you apply chroma key.
The shadow is so dark that it matches with the lines on his shirt and his hair color.Reducing the shadow will clip the person’s hair and other black areas other than shadow. The only solution to this problem is to reshoot the footage or add more lights to lighten the shadow.
As you can see in above image there are no shadows in the background but the background is unevenly lit.This is not a bad footage. But when you switch view to Screen Matte and increase the value of clip black it will destroy the pixel information to certain extent.
When there is an action to be shot in front of chroma you will encounter motion blur in a footage.In such case removing chroma becomes difficult because the blurred part blend with the green background.The solution to this is to shoot your footage at higher shutter speed.
As you can see in above image the actor is clipping out of green screen.THis happen everytime.You will need to rotoscope every part which is clipping out of chroma at 24 frames per second which will take lot of time to do.
The only solution to this is to re shoot the footage.
Not adding backlight to your subject will make it look flat in the new background. The edges will look sharp and the subject will not look like a part of that environment.
I hope this tutorial will help you save some time in your chroma effect. When you avoid these mistakes it can actually save a lot of time in post production
Image Credits – Surfaced Studio