Author Topic: Translucent PVC pendant lamp  (Read 101 times)

0 Members and 1 Guest are viewing this topic.

Offline zooropa

  • Sr. Member
  • ****
  • Posts: 368
Translucent PVC pendant lamp
« on: June 19, 2019, 05:48:52 am »

Hi again. I've been working a little bit more with the scenario and model I want to achieve. The image posted in the beginning works as a reference picture of my material/lighting goal.

This is so far where I am (using Esben lamp scene uploaded in Keyshot resources link).

As a source light for the pendant lamp I am using an Point Light Diffuse of 800 Lumens (exactly the same as the production model).
The scene has also a rectangular plane with an area light diffuse on the bright side.

The material for the shading needs to match PVC translucent sheet of .7 mm :

Translucent (Advanced)

Surface: HSV 0 . 0 . 89
Subsurface: HSV 0 . 0 . 90

Translucency 20 CM

Specular: HSV 0 . 0 . 100

Roughness: 0.1

Refractive Index 1.531

Samples 24


Material Questions:

I find it a little bit hard to guess (1 FPS) with the translucency parameter since it goes to 1000 cm as max. What do you recommend to use for a .7 mm translucent plastic shade lamp ? I think the 20 CM is not enough, it looks still not translucent in the sample. But not sure how much to crank it . My scene is extremely slow and to see changes its getting difficult time wise.



Ray bounces: 16

GI bounces: 1

Caustics ON

I think the caustics are really slowing down the render. I read the manual. If I understood right caustics in this specific render are not changing the overall look. Apparently it works with the refractions outside the volume. I am using a scene and I would also need to see how the light bounces on a table for example....should I have Caustics on or off ?

As you can see on the render sample I have some bright dots. Is this happening because of my lack of light on the scene ? How can I get rid of these?

Any idea of how to make also my scene renders faster ? Sample scene took 17 hs for 500 samples. Maybe a render farm ? Or something you could suggest that could improve the render times?

It is important to stress this renders needs to show as accurate as possible the behaivour of the light in regards of reflections/refractions.

Hope you can help me ! Thanks a lot