On the off chance anyone ever reads this : in my program Photosounder ( [link] ) I use a colour gradient to replace the black and white in pictures. Currently it's simple, it starts with dark blue, giving a nice eveningesque-nightly feel to backgrounds, then evolves towards a lighter and more intense blue, the two contrasting nicely.

It then goes towards light yellow, but with a twist. While the blue moves on seemlessly to a pastel green, instead of dully going from green to yellow, it goes imperceptibly to pastel orange, and *then* to yellow. It has the most pleasant effect of giving a yellow that comes from a warm orange, and gives it a lovely gold-like quality, despite being on a blue-cyan background.

It surely is a nice gradient, but I find it overly simple, too bidimensional at best. I've looked up some of the gradients used in technical visualisation, and they're fugly, so it's no help. Yet I think these gradients could be so much more, that we could make them into a fascinating mix of colours.. Any ideas?