Vray ........ Where has AO gone ?

[philip kelly]

It used to be in the tabs, but now i can't find it?
It was built in, is it a separate pass now?

Thank you

phil

[joconnell]

It was called detail enhancement in the irradiance map - might be in the expert or advanced mode of irmap in vray 3. Otherwise vray dirt in an extratex pass!

[Macker]

Detail enhancement did the polar opposite to AO. It takes more samples in corners, often making them lighter.

[rjohnson33]

I think you're referring to the AO that is built into the Global Illumination tab itself rather than the detail enhancement. It is still there in Vray 3 but yes, you have to be in expert mode to access.

It's always interested me as an option - you don't hear much talk about it and presume that most users looking for realism would prefer not to bake in any AO
but having said that I think the set of renders that I'm most pleased with to this day did have this option turned on. It doesn't work for many scenes but just really suited this particular one and it also created a look that I couldn't achieve in post-production
with a more standard AO applied (vray dirt in extratex). Maybe because the AO is applied at rendertime to the GI solution it's affecting just that element rather than being multiplied on top of the final beauty pass? Never been sure.

[vlado]

...rather than being multiplied on top of the final beauty pass?

But you would never multiply your final beauty with the AO (at least in theory). Only the GI render element should be multiplied.

Best regards,
Vlado

[rjohnson33]

But you would never multiply your final beauty with the AO (at least in theory). Only the GI render element should be multiplied.

Well, I suppose I've always thought of AO as more of a stylistic element rather than one with a 'proper' application but yes, I do see what you mean. As an approximation, it's an approximation of GI and should be excluded from interfering with other passes.

Is the result exactly the same in that case? (i.e. if you take the same settings from the AO in the GI tab and use in a vraydirt extratexmap - multiplied with the GI only and recompose. Should this be identical to having the option checked in the GI tab?)

[vlado]

If you go with compositing, there might be some issues with reflections/refractions. In most cases, the results will be very similar though.

Best regards,
Vlado