weird volumetric lighting glitch

Use this forum for general user support and related questions.
Forum rules
Please upload a testscene that allows developers to reproduce the problem, and attach some images.
CodeHD
Donor
Donor
Posts: 437
Joined: Tue Dec 11, 2018 12:38 pm
Location: Germany

Re: weird volumetric lighting glitch

Post by CodeHD »

FarbigeWelt wrote: Mon Jun 17, 2019 11:44 am @CodeHD, what else did you expect? If there is nothing scattering (e.g. matte, roughness, translucent, homo/hetero volume) the scene keeps black with the exception of direct light. But the latter is another story. There is no way to see ever any beam from any but direct angle in perfect vacuum. And direct means blinding depending on ‚contact‘ radius of the beam. If the surface of hitting beam covered one pixel only and intensity was only in the range of sensors sensitivity then you got one single point on your image (assuming perfect clear optics).
I expected nothing else. It was just a test to see if I could reproduce what I understood from KintuX's comment in the scene that he uploaded. I could not ;)
kintuX
Posts: 809
Joined: Wed Jan 10, 2018 2:37 am

Re: weird volumetric lighting glitch

Post by kintuX »

FarbigeWelt wrote: Mon Jun 17, 2019 11:44 am
CodeHD wrote: Mon Jun 17, 2019 10:14 am
kintuX wrote: Sun Jun 16, 2019 9:33 pm In my example, i disabled volumes altogether
If I disable all volumes, everything is really black.
Laser beams without volumetrics shouldn't be possible with the current features.
@kintuX, are you sure? One object in the scene with a material with a homo- or heterogeneous volume with scattering>0.000 is enough to get some scattered light even if all other materials have clear volumes defined one material has a homo/hetero external volume. The effect might be small but its there and visible.

@CodeHD, what else did you expect? If there is nothing scattering (e.g. matte, roughness, translucent, homo/hetero volume) the scene keeps black with the exception of direct light. But the latter is another story. There is no way to see ever any beam from any but direct angle in perfect vacuum. And direct means blinding depending on ‚contact‘ radius of the beam. If the surface of hitting beam covered one pixel only and intensity was only in the range of sensors sensitivity then you got one single point on your image (assuming perfect clear optics).
:D I know, i know.
Here's the scene file. Maybe file is corrupt, causing volume to appear out of nowhere. Maybe i missed a spot... :o
Attachments
PrismX_LC.blend
(814.54 KiB) Downloaded 140 times
CodeHD
Donor
Donor
Posts: 437
Joined: Tue Dec 11, 2018 12:38 pm
Location: Germany

Re: weird volumetric lighting glitch

Post by CodeHD »

In that scene your world volume is set to "prism volume", which seems to be a leftover because no object has it linked. Its IOR is slightly different to that of your glass prism, which is why you still get dispersion of colors.
kintuX
Posts: 809
Joined: Wed Jan 10, 2018 2:37 am

Re: weird volumetric lighting glitch

Post by kintuX »

CodeHD wrote: Mon Jun 17, 2019 6:43 pm In that scene your world volume is set to "prism volume", which seems to be a leftover because no object has it linked. Its IOR is slightly different to that of your glass prism, which is why you still get dispersion of colors.
Indeed, that's it!!! :oops: :lol:
TYVM :mrgreen:
Post Reply