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2create
02-12-2014, 05:54 AM
After feeling happy that I got Fiberfx refracting with the 'volume only' option. I now have a scattering of hot/white pixels that go over 1000% rgb values when sampling them in the image viewer.

http://louisdumont.com/files/MonstersFix.jpg

I wonder if anyone else have come across this kind of thing? No GI, Ray Recursion Limit: 20. I'm thinking it must come from refracting the fur?

Thanks for any feedback :)

MarcusM
02-12-2014, 06:11 AM
Maybe try render and export different buffers and corect this in Photoshop.

2create
02-12-2014, 07:42 AM
Thanks Marcus, want to ultimately animate them so I'm gunna keep looking for a fix in LW. Definitely something not playing nice with FiberFX and transparency.

http://louisdumont.com/files/MonstersFix2.jpg

RudySchneider
02-12-2014, 08:37 AM
If you're using Global Illumination, sometimes those hotspots can show up unless you have "Limit Dynamic Range" ticked.

omichon
02-12-2014, 08:48 AM
That would be my guess too. Take care about very high values in HDR environments.

2create
02-12-2014, 08:49 AM
No GI in the scene, 2x area lights. I've also tried the Limited Dynamic Range but have the same results :S Thanks for the help

3DGFXStudios
02-12-2014, 08:57 AM
If there's no GI it could be the light and or the shading samples being to low.

2create
02-12-2014, 09:17 AM
Thanks for the help, just tried 4 and them 12 for light and shading sample and it still has the hot spots. However they do seem to move around with the different sample numbers :S

http://louisdumont.com/files/4xsamples.jpg

3DGFXStudios
02-12-2014, 09:20 AM
Do you have very luminous polygons in your scene? Or a very tiny bump scale?

Hieron
02-12-2014, 09:37 AM
What type of transparency shader have you got there? I remember one coming up with high results (may have been a bug now fixed..), clamping it nodally worked back then but it is a while back. Is it the Fresnel like one? Clamp it to 0 and 1 and see what it does. I know it is playing nice with the backdrop, but it is worth a shot.

Also, regardless of the transparency issue, you seem to have some full white pixels near the top of your furry character.

My bet is that both are some FFX bug.. Safe bet :)

ps: Nice work! But do you need a recursion of 20?

2create
02-12-2014, 10:49 AM
Thanks guys!

I do have luminous polys to look like soft boxes and get caught in reflections and 120% Luminousity, no real tiny bump scale's. Transparency is make with gradient on incidence angle 0-100%. I was trying recursion cranked up to see if that help (which it didn't).

Did a render with FFX off and it's annoyingly fine :) might have more of a play with the FFX settings.

http://louisdumont.com/files/NoFFX.jpg

JoePoe
02-12-2014, 12:04 PM
Try Dielectric node for the glass?

Side note: They are all very cute!! it's a shame the face of the furry guy is being overwhelmed by the hair.

Sensei
02-12-2014, 12:42 PM
When sum of diffuse+specularity+reflection (and maybe +refraction) is exceeding 100%, after reflection bounces they will add up together..

If you have diffuse 100% white color, and specular 100% white color and 100% white light color, then obviously in some pixels will have 200%,200%,200% rgb values..
Then imagine what happens if other reflective surface will find it during ray-tracing and add to it's own color.

Hieron
02-12-2014, 03:00 PM
yes yes, but he knows all that.

Reproduced your bug 2create, wasn't too hard. If a thread shows "FFX" and *insert random issue* it is usually a safe bet to go directly for bughunting imho. If you delete the inner poly's on that glass surface I bet it renders fine. Damn weird bug too, it lights up the entire edge of my fur object. The same thing is showing for you, but only on specific places. Perhaps you use different sampling, AS or whatever.
Will post my simple scene so you can bug report if it indeed is the same bug (you never know with FFX!)

edit:
reproduced bug:
120140


Hot pixels showing in reflection (and changing on the fur, something is going wrong in the FFX with the bounces):
120141

Files:
120142
120143


delete the inner poly's of the glass and all is well again. Clearly a FFX bug.
I wish you good luck and hope it will be the last one you'll encounter.

ps: setting the recursion limit to 4 (just enough to pass through the glass) it is gone here too. set it to 5 and it is there.

2create
02-13-2014, 05:16 AM
Cool thanks for reproducing this Hieron, deleting the inner poly renders just fine with FFX behind :) I'll check out the scene and look to submit a bug. Thanks again!

Hieron
02-13-2014, 07:07 AM
Cool thanks for reproducing this Hieron, deleting the inner poly renders just fine with FFX behind :) I'll check out the scene and look to submit a bug. Thanks again!

No problem!

Nice work that you guys are doing btw. Will look forward to your results with this scene, hope to see it one day.