From Blackrack on discord:

Atmosphere rendering improvements: Ozone and multiple scattering

As you’ve probably noticed in the last few videos, ozone is now supported. Unlike other atmospheric components, ozone only absorbs light (mainly green) instead of scattering it. This enhances the look of sunsets, as without ozone the atmosphere takes on a greenish hue.

The first screenshot compares a sunset without ozone on the left and with ozone on the right. The second screenshot shows the ozone layer from space which can be spotted as a distinct blue band, similar to this photo from the ISS.

Multiple scattering is also now implemented and can be seen on the third screenshot. It allows light to bounce several times in the atmosphere instead of just once. This can be subtle but helps with the realism of the atmosphere. It also works well with godrays, where objects block only the first light bounce, but the atmosphere can continue to receive light from the sky itself, softening the look of atmospheric shadows. The last screenshot shows a mountain casting a shadow on the atmosphere, with both ozone and multiple scattering, similar to this photo

Additional pictures:

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