QMC setting adustments after calculating IRMAP

[Adam H. Stewart]

A tricky question, I am trying to decrease the grain in my animation. If I have already calculated the IRMAP with low QMC settings, and I render with higher QMC settings will this make any difference to the grain and noise or do I have to recalculate my IRMAP ?

Thanks for your help.

[vlado]

Re: QMC setting adustments after calculating IRMAP

A tricky question, I am trying to decrease the grain in my animation. If I have already calculated the IRMAP with low QMC settings, and I render with higher QMC settings will this make any difference to the grain and noise or do I have to recalculate my IRMAP ?

Thanks for your help.

If the saved irradiance map is not blotchy, then there is no problem to use it with different QMC settings.

Best regards,
Vlado

[Adam H. Stewart]

Thanks Vlado

Thanks Vlado, I was having a few problems saving the irmap over the network yesterday but todays tests are looking cool so far.

The question is, do you recommend lowering the QMC settings for the irmap ? - and then bumping them up for the render, it is really the grain I am worried about and trying to minimize. I currently have the QMC set to

.65
.0002
16 Samples
time independent on

I am using the standard Medium animation preset for Primary bounce
Lightcache set to World with 700 samples.

The irmap viewer was an absolute life saver as the map being saved by the net machines was way off the beam. This is my first big project using real gi and also my first HD project, I am also using HDR's with AE 7, learning on a deadline and 4 hours of sleep a night is so much fun.

Thanks for your help.

[joconnell]

Yikes - they're very low qmc settings - are you using a lot of large soft area shadows or glossy reflections? I'd probably turn time independant off personally so the grain dances - I'd rather see something that looks like a slight bit of film grain than something that looks like dirt on the screen that I can't clean off

[studioDIM]

I wouldn't look for noise in the IRmap: medium settings go to -1, meaning 2 pixels per sample.
Can't be noise once those 2px wide samples are interpolated.
Well, not HF noise AA can clean.

I'd personally do the exact opposite, lowering the QMC to something like what you have (0.0005 does it in many cases with Vlado's universal settings, for me) ONLY for the AA pass done with the QMC method.

If the noise is 1px in size, it's most likely NOT coming from your GI

Lele

[Adam H. Stewart]

Thanks

Thanks guys, the grain problem seems to have been minimized, using the settings I have, the scene I am doing is a basic city, there are three layers comped together in the background to give it a surreal glass, metal, look. The bulk of the scene is the foreground elements that are super shiny. I'll post some finished frames and maybe an animation when I am out of the three hours of sleep abyss I'm in.

Thanks again.