Hi guys,
now with all the new sampling and changes to lights etc, will i actually benefit from using vray lights set to portal mode, especially when using vray HDRI map in vray dome light?
Thanks!
M
Done some tests and in RGB pass there is no change , however the sampling rate pass looks better.
Wouldnt it be better to get rid of the skylight portal then?
And to add to this, I noticed that when using light portals it’s better to put the HDRI in the Environment slot in Max/Vray instead of a Dome light. The render just looked less noisy for the same amount of time. That’s from a quick test I did. Maybe I should double check or just try yourself so please don’t quote me on this. 
While this may work occasionally, it is not a rule and I would not recommend it. It may easily have come out way noisier, depending on how bright your HDR is.
Best regards,
Vlado
So whats the conclusion Vlado? Is it necessary to use them still or whats the benefit nowadays? Perhaps theyre only useful in some situations?
Does that mean the portal will amplify any rays that hit it from behind, regardless of source? I thought it was only environment rays (based on wording of the help, which I may have misunderstood.)
That’s the idea, generally. There are some issues when using portals together with a dome light though - the resulting illumination might not be entirely accurate. This is fixable and the fix is somewhere in a GIT branch in our code, but it’s not in any release yet. Hopefully I will be able to finish it for 3.6. For the moment though, if you are using a dome light, then it would be better not to use portals at all.
Best regards,
Vlado
That’s interesting. Makes sense, thank you.
vlado,does the issues when using portals together with a dome light still exists? or is it safe to use it with 3.6?
There are still issues. Which is partly why I want to get rid of them
Best regards,
Vlado
They are already working on exactly that, as far as I remember.
Dear Chaos team,
I asked chatgpt and it said that it makes sense to combine Arealights with skylightportal mode to enhance GI being cast from a Vraydomelight with a connected Vraysky to get better GI and reflection samples in the same amount of time. Vraysky just on the domelight, not in the environment slot. Even if that Domelight is adaptive.
I am not sure if I can trust chatgpt on that. 
Would you agree? Especially since that skylight-portal option is only accessible per script.
Since our aircraft scenes have tiny windows, this might make sense?
Rendering still with VRay 5.x, Bruteforce, Lightcache and Denoiser.
Vlado posted in 2017 here that there were issues that he were working on. Is that solved?
Thanks
Robert
Since the introduction of Adaptive Lights in V-Ray 5, there’s no need for Skylight Portals. I haven’t seen anybody using them in ages, and I recommend you don’t, too.
Don’t ask chatGPT. 