I bought a sheet of fluoro green card to use as a green screen, and tried it out with this Reaper Ettin. Then I removed the background using Photoshop's colour range selection.
It was not a complete success, though to be fair it was a pretty bodged-together job, and it might be better with a bit more forethought and effort.
I would need to adjust the lighting to remove as much shadowing as I can for a start, though that doesn't address the biggest problem, which is colour reflection on the model itself. It would also be useful to be able to take spot light readings, but my camera isn't really that clever — I'd have to adjust exposure manually, by trial and error, or else rely on its bracketing feature (which I'd have to set manually anyway).
|With green screen|
|Green background removed|
|Levels and saturation adjusted, layer defringed, new background added.|
It hasn't been a worthless experiment by any means. I'm not precisely sure how to deal with the reflection issues, but possibly a variety of background colours to suit individual subjects might be a solution? maybe.
Hmmmm..... one thought occurs to me: perhaps if I bring the model forward, out of the immediate reflection zone, and put it on a green-painted pedestal so that I retain the green background without contaminating the model itself? It's worth a try I think.