will a cleaner LC-[Secondary bounce] make Brute Force [Primary bouce] cleaner?

V-Ray V-Ray Common Render Theory
1

Hi All,
Just a quick question regarding Secondary GI solution & it’s affect on Primary GI

Does it make sense that the Primary GI engine will be cleaner/faster if the secondary bounce solution is cleaner.??

will a cleaner LC- make Brute Force cleaner?

will a cleaner LC- make Irradiance map cleaner?

Cheers
Jamie

2

No - the two are using different techniques to achieve different things - the secondary bounce wants a very smooth overall solution whereas the primary wants a very sharp, detailed solution so trying to get one close to the other would be a little counter productive. One thing of note though is that with vray with the qmc sampler affecting a lot of sampling throughout every aspect, changing the settings to improve one part may also up the settings of another giving the impression of what you’re talking about.

3

Thanks joconnell!

I am still a bit confused though.

Does the Primary bounce & secondary bounce get ‘added’ together to get the final pixel value??

Cheers
Jamie

4

Yeah pretty much - light is always additive so one goes on top of the other alright. They’re calculated differently but the two get added together at the end so if you’ve a grainy brute force it’ll add grain on to the lc - likewise an lc with errors / mottling will show under the brute force. I’ll do a proper post on the gi methods soon.

5

Thanks so much again:smile:

Sorry if my first question was not so clear.
I guess if I had framed the question better the first time I would have got the answer you just gave…without wasting too much of your time:face_with_spiral_eyes:

Cheers

6

All good dude!