Author Topic: Improved Sun & Sky model playground!  (Read 20582 times)

2020-08-22, 14:37:15
Reply #90

pokoy

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The new sky feels quite pale to me. Will the turbidity allow for a richer blue? Im currently switching between a clear blue pg skies hdri and the corona sun/sky and the latter is much more washed out and creates a flatter image out of the box without additional tone mapping. Good idea to use the colour correct node, does that effect performance?

Turbidity will probably make it less blue since it adds atmosphere fog/humidity. How blue the sky appears depends a lot on the viewing angle and fov. Sky is mostly dull towards the horizon, and if you use a tele lens it might turn out as light blue in such situations.
You can use a color corrected version of the same sky map in the background override only if it helps, make sure to instance it so it uses the exact same map.

2020-08-24, 11:28:36
Reply #91

Rhodesy

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I suppose if we could consider the current sky system as a mid point in terms of turbidity in the slider, I'm assuming we could always reduce the amount of turbidity to create that pure blue sky? Its true about the field of view making a difference and the location of the sun in the sky but its in the reflections of glass and metals that a sky with the option of a bolder colour tone would really benefit.

By increasing the colour saturation in the colour correct node for the sky it can bring out other colours like a pink band which is undesirable so hopefully a new system will negate the need to do this.

Trying to get a sky as rich as the attached photo is a struggle with the current system so hopefully the turbidity slider will solve this.

2020-08-24, 12:05:24
Reply #92

pokoy

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If I remember correctly, the new OSL color correct map has an option to color correct only certain hues, might be worth trying if you're on Max 2019+... not sure if it really does this, though.

Another thing, but it depends on how true to world the new sky model is, the sky is always darker in opposition to the sun. It's the same in your example, the sun is behind the camera, lit objects are brighter causing shorter exposure/closing the aperture and making the sky darker/richer in return.

One important aspect to remember is tone mapping and color processing. The blue will vary depending on camera manufacturer/model so the result of what your camera 'sees' is pretty much an arbitrary decision made by the manufacturer. It can't really look the way colors are because they are interpreted by the camera's hardware and software. Even if the 'spectral color' in the photo and the sky map were the same you would not get the same output from the renderer unless all the color math is identical. That's why tone mapping and LUTs are such a vital part of the color discussion.

However, I totally see why you want to do this... Yeah, keying out certain hues and being able to color correct them is important every now and then.