first off, turn your camera’s auto gain off, and go full manual.
Back in the day before reelsmart motion blur and such, keying was jerky looking from shooting with a really high shutter. Now you can post-add the blur back in.
And don’t go the other extreme; shooting with super bright lights and stopping down the camera to f/12. You’ll get a problem called “circle of confusion”, yes it’s real!
You actually reduce image quality because light is bouncing off the diameter lens. That’s one reason why movies are shot f/5.6. or less.
Another advantage is you get a shallow depth of field which blurs the green screen to make much better keys. If you have too, at least use a Neutral Density filter.
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