Wesley,
This is my take on it and I agree with the other gentleman’s response that it was probably done using a Colorama filter. It looks to me like he/she roto-masked the hand out and then color mapped, using Colorama. The biggest trick though and why the midas hand works is really because of the placement of the highlights and shadows on the original hand. So you have to watch your lighting and you want to map to luminescence or brightness. I would also note that this is working because the hand is relatively stable and less problematic than a regular hand held cam shot. When imagining what some of your shots might be like with students painting the walls, I think realistically, you’d have to isolate very carefully the way you are going to use the effect and create the feeling that, if this is what you are going for, the effect happening consistently through out. The other “trick” would be create a lot of anticipation, showing the color about to splash on to the subjects without actually showing the effect.
Scott Lange
Burst FX
scott@turbulenceffects.com