Arnold Mirror light rays reflection

[Anonymous]

Hello, i need help, i'm trying to get light rays getting reflected into a mirror with an AiAtmosphere.

But when i set up the scene with a plane (the mirror with aiStandardSurface preset chrome) and a spot light shaped like a lazer, i can see the ray on the mirror but the ray doesnt rebound like the example below.

Example 

[mspeer · Accepted solution]

Hi!

You can't do something like this with Arnold.

[Anonymous]

Ok thanks for the reply 🙂

[zambetti]

So, to confirm, there is absolutely no way, in Arnold, to trace light rays leaving a "mirror" surface to their destination - like in in this Iray example: a large mirror reflecting sun light onto a tower (sky removed for clarity).

[toby.gainesQTXCX]

Try caustics? I've done that in other renderers... but this is arnold, so yea it probably won't work 

[zambetti]

I did. Not working,  Usually caustics needs to be on, like in Iray above. I also had done it with Mentalray and it worked. Not with Arnold, apparently.

[toby.gainesQTXCX]

yea I just tried it too - utter failure - why the hell does anyone use this crap, there's literally 0 benefits to it, except maybe to pipeline. Nerds love it, who cares if it's the slowest and noisiest renderer of all, and crashes constantly - to hell with everyone else, incl. the final customer, the audience

[toby.gainesQTXCX]

I searched the help - there's nothing but a bunch of articles on how to FAKE caustics. And one on refractive caustics, nothing on reflective. 

It does reflective caustic completely wrong. I focused a light with 0 spread, on a mirror with 0 roughness, and the only light that came from the caustics was 100% soft, broad, unfocused light. 

Like typical Autodesk they probably just have 1 guy working on features / bugs. And all they care about is pipeline tools like Operators, nm that the renderer is trash. 

[zambetti]

That is consistent with what I have experienced. Too bad.