Emissive in Iray caps out and is not nearly strong enough for certain renders.
You can normally only get the strength to "1" using the sliders in Iray mode.
It is possible to get the emissive to "100" if you set it in painter mode and then swap to Iray mode.
(this is a bug, but it works in my favor)
However, even the "100" is a hard cap that sometimes isn't enough.
I'm currently trying to render a car, where the headlights needs to be much brighter than what the emissive setting allows me to set.
Since real headlights have pretty small but very strong lightbulbs, they use reflectors to boost that light even more to get sufficient brightness. Even with a reflector being 100% metallic, with 0 roughness, the bounce light is not strong enough whit the emissive getting capped at "100" in painters Iray mode.
I also use emissive materials to create bounce lighting in some cases. I can add a surface and add an emissive material to it to simulate light sources in my scene. If I get more control over my emissive materials the Iray mode would be much more powerful and I could use it for many more of my renders.
One approach could also be to get a separate exposure for the environment and the camera. That way I could lower the exposure of the environment, but boost the exposure in camera, to balance brightness between the HDRI and the brightest emissive source without getting a very dark image that just looks underexposed, instead of overexposed lightbulbs.
(EV on HDRI lowered to -2.5)
Looking forward to your reply, solution, or potential work around.
Cheers,
-Ludde
-Ludde
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