typical black blotches in light cache

Hi everybody,

we have recently switched from irradiance map + QMC to irr map + LC. It’s much more faster (rendering and preparing the vrmap) but we have som quality problems. We’ve been checking every parameter but maybe not the correct way. Do you know how can we reduce this black blotches? I also attach the rendering setup.

We only have this problem when preparing a vrmap every 5 frames. If we render a single frame it’s perfect.

Thanks!


Alex[/img]

i dont know if those are LC splotches, your irradiance map is extreamly low quality

after adjusting your irrad map, if you still have splotches, raise your hsph subdivs, they look low.

…and change the scale in the lightcache from world to screen or raise the sample size to 4 for example…

best regards
themaxxer

Seems like splotches go from irrmap. Very low. (maybe… there’s a world scale in LC, that makes samples a lil bigger than expected)
For LC - try default settings, as they seem to be more than enough.

its interpolating alot of your samples when you have it up at 40 but you dont have many samples to interpolate so things would look kinda slotchy. i usually go with something like 60/30 or up to 90/30

thanks a lot! i’m going to try it now and i’ll tell you in a while.

ALex

I’m back. I’ve been testing this and with irr map to -3 -1, hsph 50 interp. 30 and LC subdivs 500 world and i get this (worst than the other one):

This is a 450 frames animation. As I told you, when I render only one frame without vrmap file, it’s perfect. The problem comes when i make the vrmap (every 5 frames) and then i render the frame (for example) 260.

Thanks!

ALex

Can you post one frame with light cache/light cache only?

Best regards,
Vlado

did you set the lightcache to flytrough? if so, you need much more subdiv e.g 2000

best regards
themaxxer

I suppose there might be some geometry problems as well.
Such leaks often appear with bad geometry.
Is this a MAX model or some CAD stuff ?

Best regards,
nikki Candelero

are those walls on the right foliage (only one polygon) or solid (like box)?
and are present some coplanr polygon?
From artifacts on the tiles in bathroom or kitchen at the left of the image seems u modeled this tiles are them face to face to wall? if yes detach the tiles object from wall a little or put it a little inside the wall
I’d look to geometry model before to the parameters as Nikki told above too
good luck and let us know the cause

hi again,

your requests:

frame crisis v4:

and a vrmap file if you want to see it:
http://clients.4dvirtual.info/vray/OPCION2\_CAM\_2\_alex03.zip

your questions:
- yes, lightcache is to flythrough
- i think geometry may not be. We’ve repeat that wall at least one million times :-). It’s all 3dsmax (not CAD stuff) and all intersections are correct.
- there aren’t any coplanar polygons, and it’s not foliage wall XD.. Tiles are not modeled, it’s a bump map.
this is the plan view.

this is an image of the toilet. You can also see the problems in the tiles as you said (it’s not exactly the same frame):


Thanks a lot,

ALex

something I sometimes do when troubleshooting is to try a render with irradiance map for first bounce and QMC for second bounce. If the splotches go away then it was most likely linked to your lightcache settings.

yes, you are right. In fact this is the first project we are doing with LC. We always work with IRR+QMC, and in fact we don’t have this artifacts with QMC. It may be something related to LC, but i don’t know. Maybe the combination…

Alex

did u check this?
if u set ur LC to 500 in flythrough mode ur definettely gonna have pretty low samples through out the flythrough!
:wink:

Yeah turn flythru on, set scale to world and put like 3000 subdivs.
I would suggest untick store direct light and change filter to fixed as well.

See if that helps.

this is the result with your values DaForce (we were already using World and flythrough) but i have switched the other options.

what do you think?

of course i have to make all the irr map calculation (for the 450 frames), otherwise there’s no problem. If i make a 50 frame or less part it’s ok. The problem comes when it’s for all the animation.

Thanks!

ALex

i still think u need more samples in that LC…
personally i ve ditched flythroug mode on animations to calculate each nth frame in order to have more control over it… :wink:

did you try raising hemispherical subdivisions as several people have already suggested?. Also the frame looks very blurry so i think 40 is too high for interp samples. id also raise your max rate from -3 to at least -2.

Other than that, its most likely lightcache settings as mentioned I think (more subdivisions)