IES Lights

[GALACTUS]

Hi

I have just started testing Lavina this morning and it is great.

Below are some of the issues/quirks I have just encountered.

1. IES Lights instanced in 3dsMax are not instanced in Lavina.
2. Object with VRay Light Material converted to actual light in Lavina. (might be how its meant to work)
3. The intensity value of IES Lights set to 0 and even increasing any of them to the max value of 100 had no impact on the scene.

Really loving the software even though I have only been on it for 30mins...great work.

[vladimir.nedev]

1. IES Lights instanced in 3dsMax are not instanced in Lavina.

Light instancing is on the TODO list, however, I am pretty sure light instance information is currently not stored in the .vrscene file, so we might have to update the exporters as well.

2. Object with VRay Light Material converted to actual light in Lavina. (might be how its meant to work)

If you have Direct Illumination set to On in the VRay Light Material, the .vrscene exporter in 3ds Max is probably converting the mesh with that light material to a mesh light.
Currently we don't support mesh lights.

3. The intensity value of IES Lights set to 0 and even increasing any of them to the max value of 100 had no impact on the scene.

We don't support IES lights in this version, but they are on the "very important" list of things to add support for.
Hopefully, this will happen in one of our next beta releases.

Greetings,
Vladimir Nedev

[GALACTUS]

Cool, thanks for the feedback, will bear that in mind and adjust scene accordingly.

As I said before...Great stuff really.

Cheers

[vladimir.nedev]

The latest version of Lavina has support for IES lights.
They should work now with the proper intensity/power loaded from the .vrscene.

Greetings,
Vladimir Nedev

[max_romju]

Hi vladimir.nedev
version 1.4.2
there are some wrong still,as the photo ,the vantage ies effect is weaker than vray, and the position is lower.How can I improve it?

thanks.

[Alexander.Atanasov]

Hi max_romju,

This is possibly caused by Clamp secondary rays option. It suppresses the contribution of very bright secondary(GI/reflection/refraction) rays, which may typically cause excessive noise (fireflies). When enabled, the scene may turn out to be darker than the actual correct result. You can turn it off or increase its value in the Render tab.

Best regards,
Alexander

[npg]

The angle does look different though. Could you share the IES file? Is there glass in front of the IES light?

[max_romju]

nothing In front,(I have replaced them for test);
the ies content:
IESNA91
[TEST]2991-1
[MANUFAC]KURT VERSEN
[LUMCAT]B7424
[LUMINAIRE]DIRECTIONAL
[LAMPCAT] Q150W PAR-38 SP
[LAMP]
TILT=NONE
1 2500 1 19 1 1 1 -.6 0.00 0
1 1 150
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90
0
19011 10640 4455 1289 540 391 295 219 69 45 31 0 0 0 0 0 0 0 0

[vladimir.nedev]

We need the original 3dsMax scene and the IES file in order to test what's wrong.

Greetings,
Vladimir Nedev

[npg]

Alex already tried the IES file in isolation. It renders pretty much identical in 3dsmax and Vantage (Vantage has slightly softer transitions, this was known from before).

The screenshot below the IES file contents shows gizmos for the lights that seem misaligned relative to the white circles. It seems the positions of the lights are different in Vantage and that is why the wall is lit differently.

[max_romju]

Hi,guys,Thank you very much
I Upload a simple max scene,(max version2020,vray 5.1.2), vrscene has been exported by right this max scene.

[npg]

Thank you for the scene. The issue is caused by the shadow bias parameter. When you set it to zero, the renders match. We will look into it.

[npg]

There is a known issue in V-Ray that V-Ray Standalone (CPU) doesn't match V-Ray in 3ds Max when using non-zero shadow bias. I don't know how/when this will be solved.

Vantage renders it like V-Ray Standalone CPU.

[vladimir.nedev]

You don't have to set it to exactly 0, a very small value like 0.001m should be close enough and prevent self intersection.

The shadow bias is supposed to be a small value, 20cms like in your case is way too large and currently causes differences when rendering in V-Ray Standalone (Cloud) or V-Ray GPU as well.
In general, you should avoid using large values for the shadow bias.

Greetings,
Vladimir Nedev

[vladimir.nedev]

In general, you should avoid using large values for the shadow bias.

Sorry, I thought you set the value to 0.2m yourself, but I guess you didn't do that and this is caused by the system units being meters combined with the default value of 0.2.

We will need to investigate a solution to this in V-Ray for 3ds Max. For now, you can manually lower the value to 0.001m (for example) when creating new lights.

Greetings,
Vladimir Nedev