Rainbow query

[pquinlan]

I like rainbows and know a bit about them: circle around a line between your head and the sun, secondary inverted rainbow, and so on. But I have often noticed (esp when a lot of dark cloud behind it) that the sky outside a rainbow is significantly darker than the sky inside (or is it vice versa?). Anybody know the explanation for this?

[mibn2cweus]

Raindrops do not reflect light in this region:

Alexander's Band

[ian.miller]

The only thing about rainbows I remember is from an old Open University programme that the angle from your viewpoint to the top of the rainbow will always be the same, 42' I think.

And that no two people actually see the same rainbow, everyone sees their own.

[Geo1000]

The sky outside the rainbow will be its nornal darkness. I think the raindrops below the bow will be scattering light back to the eye, but not at the precise angles that give the rainbow its colours. The scattering is more random hence the 'whiter' colour.