Suzzane:

Strangely enough, it IS possible to distinguish the differences among 32000 colors. Even 32000 colors are not enough to capture the subtle gradients of, say, a sunset. In fact, the human eye can distinguish a whopping TEN MILLION different hues and shades of color!

On my computer I routinely switch between 256 color mode and 32000 (or is it 65536?) color mode. The difference, subtle at first, I now find striking. And there is even a noticible difference between that and the next highest level, 24 bit color (millions of colors).

All of this gives me new respect for the sky and for the eyes which watch it.