realistic lighting?

[Anonymous]

Hi

We're just starting to play with proper rendering in AC10.

The lighting looks terrible. Any tips on getting more realistic lighting? The lights available in the library seem very limited.

TIA

Adri

[__archiben]

andyro wrote:
What specific influence does location have besides latitude? Is there someone deciding what the quality of light in Abu Dhabi, Blenheim or San Francisco is?

i don't think so, (and really hope not!) but when i changed my settings to match dwight's the lime green turned to yellow.

switching back to 'blenheim' now stays with the yellow, so that was a red-herring . . .

[Dwight]

I never put the ambient value over 40.

The ambient and sun colors I sample from adjacent building faces.

Slight yellow for sun - brown in California.
Grey blue to Mauve for ambient.

BTW: I think this bug is only in OpenGL.
Have you tried any LightWorks renderings to see?

Andy: Geography differences only affect the sun study angles...

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Dwight wrote:
Have you tried any LightWorks renderings to see?

yep - same deal. the sunlight colour pervades the entire project.

[__archiben]

another issue that is closely related to how materials are rendered using luminance values from the built-in sun concerns the sun altitude angle: if the sun is between 0º and 44.9999º vertical surfaces are lit with far more luminance than if the sun angle is somewhere between 45º and 89.9999º. correct me if i'm wrong, but this is extremely BAD! it seems there are simply only two states for how a material renders based on the sun altitude angle alone. i've only really noticed this properly using the 'realistic sun' shader in AC10. it may have been present earlier, but has never been so pronounced.

this needs fixing urgently as it is currently impossible to do a true sun study render and have the surfaces illuminated with any degree of decent aesthetic quality!

[Dwight]

Weakness of oblique light angle rendering as you indicate is a dramatic and persistent problem in the LightWorks implementation.

Users experiencing this phenomenon should increase the roughness of wall surfaces to compensate.

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Dwight wrote:
I never put the ambient value over 40.

with the sun on 100% and ambient on 40% . . .

once the 'contribution to ambient' reaches 63% the light quality reduces - no weird colours though.

[Dwight]

I don't have experience with these extreme settings.

[Dwight]

BTW: In the Sun Shader dialog - is your sun color temperature set to 0.0??

[__archiben]

Users experiencing this phenomenon should increase the roughness of wall surfaces to compensate.

does that involve using a different reflectance shader than 'matte', or should i be using the 'rough' displacement shader?

Dwight wrote:
I don't have experience with these extreme settings.

ouch! just experimenting...

BTW: In the Sun Shader dialog - is your sun color temperature set to 0.0??

yep - but that's a "sun" shader setting right? mine was on "realistic sun" by default. unless i'm looking in the wrong place?

ben

[__archiben]

here's a new one....