Widnows 10, ATI HD7750
Short description of error
Hosek/Wilkie sky model has wrong "greeny" sun glow coloration. It's visible with turbidity set to 2, 4 and 6. That halo should be white-blue. Ground color can be set from 0.0 to 1.0 so it should be always "grey" but when turbidity is set about 8 changing ground albedo causes ground coloration from pink to blue. Besides original model allows to set RGB ground color, in blender only monochromatic albedo can be set.
Here is original model documentation and none of this can be seen (please take a look @ page 9 for albedo setting):
I think that original sky model was introduced in blender in 2012 but model was updated later and not updated in blender.
Additionally some enhancements could be made:
- Sun color node. That would control temperature and intensity of sun depending on angle and turbidity to get near-natural complete sun-sky lighting (now we have to eyeball sun temperature and intensity). That could also control "limb darkening" effect as in original model: (from: http://cgg.mff.cuni.cz/projects/SkylightModelling/ ):
- Allow direct visibility of sun lightsource to allow bloom/glare do their job and make nice sunstars directly in compositor
Exact steps for others to reproduce the error
Please open attached file. It's simplest "cube" scene with two cameras pointing sky and ground. Just render and see.