Prismatic Layers Of Air In Tuscany from My Modern Met

In Western cultures at least, little kids first learn to draw with a blue or (black for night-time) sky, and a yellow orb for the sun. In reality, sky can be many different colours (and the sun is white, but that’s a different blog post).

Why is the night sky turning red? from Discover Magazine

Watch As Clouds Convince You You’re Underwater from io9

Why Is The Sky Blue? from The Explainer

The illusion that lets you see ghosts of clouds, from io9

Clouds that look like a surrealist painting from Lost at E Minor

Changing the colour of the sky is a great way to significantly alter the mood of an illustration. A blue sky is cheerful, a stormy sky foreboding, an orange sky indicates evening, or early morning, and a purple sky might convety a fantastical or magic world.

What if you change the colour of the sky after the rest of the artwork has been done? I read a hint lately in a digital art manual which suggested filling a top layer with the colour of your sky, then setting it to multiply blend mode. This will tint the landscape/cityscape or whatever to the appropriate hue, since the colour of the landscape is influenced by the colour of the sky above. I haven’t had a chance to put this to use, but I did try it out anyway on an illustration I’d already done, and I do believe it would be a good way to get the sky matching the landscape, if you end up with a hue which draws attention to itself, or in which the sky looks somehow separate from the land.