Render yellow colored object as blue (design oriented question)

Question

So I've got this dune I want to make in 3D. I made it a yellow/orange albedo simple material. The thing is that I want to find a lighting that renders is as dark blue/purple color as if I was watching the sand at night. But whatever configuration I try, the best color I can get close to it is somewhat of a dark red (wine) color. Is there something I'm missing or must I do some clever tricks with textures to make this happen?

So this is the "sun" (everything is default now except the color)

And this is the material of the sand. (same here: default except for what you see)

These are the last changes I landed on after trying a bunch of things.

Answer 1

When using colored light, you have to remember that it affects the color of objects. If you use a blue light in real life, most colors will not appear correctly. If you look at the color chart on this page:

http://www.d.umn.edu/~mharvey/handbook5607.html

...you can see that under blue light, red, green, and yellow pigments will appear black. Orange pigment appears dark brown. Others just appear blue or darker blue. It's just the science of light.

Here's a scene in Blender with pure white light:

The same scene with blue light:

and green:

and red:

If you must use a blue light, I'd make your dunes white or a shade of gray instead of yellowish-orange.

However, most scenes aren't lit with a single light source. What you could do is add a touch of "moonlight" by adding a second light. Here I made the blue light a "hemi" light, and then added a "sun" light that is light gray:

It's still blue and dark, but you can see the different colors again.

Answer 2

Don't do anything with the light, leave it white. In Cycles, apply Invert node to your object's material color (you can make adjustments with the slider). Don't forget to change the world's color, too, as appropriate. Dale's method doesn't change the tint. Although it's darker, yellow is still yellow and you want blue