I recently began working on a project that required green screening a puppet, using my new Mac computer and my newly acquired issue of Dragonframe 4. I ran into trouble trying to get the color I wanted to key out.
I got direct help from one of the guys at Dragonframe to show me how to do it and I was enormously grateful for the live assistance. He hooked into my computer and set the key settings for me and all was good. But on the very next shot, I encountered the same problem.
Knowing it was something I was doing wrong and that the software would in fact do it, l pressed on trying to figure out what the problem could possibly be...
SPEED, that's the issue. For some reason, the eyedropper tool requires you to pick the color you want to extract from the shot very rapidly. I got it to work after recalling what I saw the guy from Dragonframe (Dyami) doing on my screen when we linked out two computers together. I did all the same step he did but he did them much faster than I did. So I tried doing it very quickly... and it finally worked!
So if you're out there ripping your hair out with the same problem, the solution is this - tap the eyedropper tool and then quickly tap on the color in the scene you want to remove immediately. Don't wait a heartbeat or Dragonframe will forget what you're trying to do.
Great advice, thanks. And the history lesson. Actually I am using a blue screen as a sky background quite a lot, but hadn't considered it for use as a small screen.
I've wondered if it might be a good idea to use a white screen and project the needed color onto it instead of picking a pre-colored screen. It would be possible to take a photo of the objects being keyed, blend all those colors together then flip it to the inverse color and use that to project on the screen... which would be the best possible color to key with ever. :)