V-Ray Light, Affect Specular/Reflections - Getting old behavior back?

[JonasNöll]

Oh wow awesome, let me prepare the scene for you and send it to you!
For V-Ray 5 I am using 3ds Max 2021 latest ServicePack and stuff...

[JonasNöll]

Alright, I sent you the scene. Let me know if there are any issues and would be really interested to try out this experimental built

[JonasNöll]

Hi, so this here is basically the setup I am talking about. Should be pretty standard situation:
It seeks to emulate the same thing like what is possible in Corona:
The problem is that in later V-Ray versions because of the way how the specular/refllection in the lights are handled it is not possible to get the specular from the domelight. Only the diffuse lighting will come through. The specular is being blocked by the environment.
The workaround is to manually add a new light inside the geometry dome and have it emit specular only but the specular doesn't match the position of the domelight because that is infinitely far away.
In 3.6 this is no problem and the specular can go "through" the dome geometry.
Anyone has an idea how to not require this additional light inside the dome and use the specular from the domelight? The idea is basically to ONLY use one domelight in the scene. And there should be diffuse lighting, specular highlight from the sun coming from the VRayDomeLight and reflection from the dome geometry.

[dreidesign]

Did anyone found a fix for this "issue"? We also got the problem with one particular scene, which was created a few years ago with the prior v-ray version. Now we need to rerender some shots, but lights, reflections are totally off. Only way to fix this is to temporary reinstall the old vray version just for that particular project.

[JonasNöll]

I was told that they are working on something, but so far I didn't get any solution in my case yet. But I was also told the previous behavior is not coming back, so I wonder what the fix would be then.
I still didn*t really understand what the new "Affect reflections" actually is supposed to do now. According to the doc it "Specifies whether the light source appears in reflections." Well that's what it did before and now it normally doesn't do anything at all and only if your glossiness in the material is above a certain treshhold.
And Affect Specular does both now, specular and reflections. Would really like to understand what is the benefit of doing it this way now. It just seems less flexible to me than before. I never had any issue where specular and reflections didn't match, but I have lots of potential issues now if I can't control them seperately anymore.

[kosso_olli]

Would really like to understand what is the benefit of doing it this way now.

Vlado is talking about that here: https://youtu.be/qUiErfgaIKg?t=67

[JonasNöll]

Awesome, thx for the video and explanation. I can can relate to the reason it was done but from my perspective in my workflows it never posed any issue and the new way does, but if the majority of users can benefit from it the new way I will try to live with it I just feel I lose ton of flexibility like this way. I also think compositors would much more prefer to be able to have one separate pass for specular and reflection. Now the specular and half of the reflection is in the specular pass and the other half reflection is in the reflection pass. Not really logical from my view, but I'm not a compositor so maybe compositors love to have it that way.

Just need to have a solution about how to put a simple model in an HDRI environment then, because now you can either have an infinitely far away domelight with a groundprojection that doesn't work, OR you build a custom projection but then need to give up on your specular from the domelight. So both ways kind of don't work.
Disabeling the Consistent lighting elements switches back the passes to how they worked previously, but unfortunately the same thing doesn't work with how the light reflections/specular are treated, so in my case that is unfortunate.

[kosso_olli]

Now the specular and half of the reflection is in the specular pass and the other half reflection is in the reflection pass. Not really logical from my view, but I'm not a compositor so maybe compositors love to have it that way.

Think of it this way: Specular layer has all the reflections and speculars created by direct lights sources, inluding HDRI (Arealight, Spherelight, Disclight, Domelight etc), while the reflection layer only has the reflections happening between objects (a teapot reflecting in another teapot, or the spout and handle of the same teapot reflecting in its body. This behaviour now is consistent with any other render engine out there. V-Ray was an outlier there in the past.
We too thought that this would have an impact on our workflow, but so far it did not.

Just need to have a solution about how to put a simple model in an HDRI environment then, because now you can either have an infinitely far away domelight with a groundprojection that doesn't work

I do hope there will be a solution. Could you try out the build Vlado offered?

[JonasNöll]

I do hope there will be a solution. Could you try out the build Vlado offered?

So far I didn't receive any different build. Just got the info that it's aparently being worked on but thats all I know

[JonasNöll]

Hi, it's been a while and unfortunately no solution so far. Is there any update if or when there would be a solution for this issue? Thx