Whenever I try to take pictures of actors in a stage show, the colors always end up looking wrong. I assume it's something to do with the abnormal lighting—we don't have peach, blue, green, and amber light shining on us in "real life", after all—but I'm not sure how to compensate for the difference between what the camera expects and what it gets from a stage.
I shoot in JPEG using a Canon PowerShot SD750. Not the most advanced camera in the world, but I have been toying with CHDK on it.
Generally speaking, stage lighting is tungsten in origin. As such, I recommend setting your white-balance to that. Sure, the gels are going to give all sorts of other colors, but if your settings match what the actual lights are, you'll have the best chances at a reasonable facsimile of what your eyes were seeing.
And yes, if you can shoot RAW (with CHDK, in your case), that will help you be more able to fine-tune, handle the edges of the dynamic range, etc.
Happy shooting!
The best advice I can give is to shoot Raw. The white balance under theatre lighting is often so far from what you encounter with normal shooting that one of the colour channels (usually the red channel) clips (becomes overexposed) which prevents further editing.
I'm afraid this approach will require more time in editing but there's not much you can do as the camera can't expect to do white balance by itself under these conditions.
edit just read your comment.
Without shooting Raw you don't have many options I'm afraid. You could attempt to set a custom white balance but the conditions will be constantly changing. You could also edit the JPEGs but you have limited ability due to the problem of clipping colour channels due to extreme colour casts.
First of all, don't use Auto White Balance.
You'll probably want to go with tungsten, but even setting the white balance to flash or daylight will be better than auto. Even if the color is a little off, if you've set the balance to something that is close, then the colored lights will have the correct effect, and the camera will not attempt to correct for the cast (that should be there).
Of course the best results will be from shooting raw, making minor corrections in post, but even then you will want to set the mode to the closest color for the ambient (non-colored) lighting.
In order to photograph live stage shows you may need:
Tools
Again, these are just tools.
Adjust ISO/ASA
After a little research. If you're able to adjust the iso/asa to a 800/1600 rating you maybe able to snap photos with a higher shutterspeed; thus all your pictures won't turn blurry
DSLR
Unfortunately, you may grow out and of your camera at some point.
The best photos may allow you more granularity and control of Depth of field, focus, shutter speed, etc.
So considering a DSLR at some point maybe an important decision. This will allow you limitless artistic license.
