When shooting chromakey footage (green screen or blue screen), here are a few short camera exposure tips to ensure your keyed footage is the best that it can be.

Note the super clean green screen. Gaffer, Dan Juenemann (left). Actor, Ricky Wang (center). DP, Marco Solorio (right). Sony EX1 via 10-bit HD-SDI to an AJA Ki Pro using ProRes 422 HQ.

Stop down your lens
I personally LOVE to shoot wide open (narrow depth of field), but on a chromakey set, I like to stop down the aperture. This will make the talent sharp, including their hair. If you don’t stop down and the hair is too soft from narrow depth-of-field, the keyer will have a tougher time trying to key it. Do try to distance the talent from the green/blue screen so that if there is any blurriness beyond their focus zone, the green/blue screen will at least benefit from being a little soft.

Faster shutter speeds
If your shot can get away with using a faster shutter speed without losing the aesthetic of the overall scene, then do it. You’ll pull a much cleaner key if your keyer isn’t dealing with motion blur, especially between moving fingers where it’s most problematic.

Gaffer, Dan Juenemann (left). Actor, Jeffrey Weissman (center). DP, Marco Solorio (right).

Low gain/ISO
Always try to keep your noise level down so your keyer isn’t dealing with unnecessary noise levels, as some cameras will introduce colored noise, something we obviously want to stay away from for our green or blue background.

So if you’re going to stop down your lens, increase the shutter speed and lower the gain/ISO, you’ll have to make sure you have a LOT of light for this, for both the green/blue screen and the talent. If you’re finding you don’t have enough light for everything, try slowing down the shutter speed first and go from there. If you’re using a camera with a large image sensor and clean ISO ratings from 100 up to around 1600 ISO, then try increasing the ISO first.

Happy keying!