Does anybody have any technecal knowledge of the process behind inverting colors? I imagine it would be pretty simple. I'm wondering about this because I got a new HP photoscanner and scanned some B&W negatives with it. The scanning screen had an option to inver colors but I wanted to do it later and could not find that option anywhere in the software after scanning. I thought, "Well, this is interesting. I'll just use Picasa. It starts up really quickly and I can organize the scans really easily." Picasa can do all kinds of neat tricks, but not invert colors. Why it that the only programs I have that can invert colors are either really complex, expensive, and take a long time to start or free and practically useless(MS Paint)?