Sky. I've been asked "was it really that bright and colourful?"
~ Yes it was!
If the air scatters shorter wavelengths more efficiently than longer
ones, why is clear sky not violet rather than blue? It appears so
because sunlight does not contain much violet and the eye is not very
sensitive to it.
Jan 26th 2003, sun's centre 3°
below the horizon.
1/30s f/2.8 100 ISO equiv. 2 images each 35mm efl. Approximate FOV
Photo ©2003 Les Cowley