How to make this special plexiglas


I would like to make this shader, a plexiglas with a colouring of the sheet that is so small that the material hardly seems coloured except for the edge.
Is-there a way to make something like that? :blush:

What you need is Volume Absorption. Add it to a glass shader and you should be quite close.

Something like this. The Ray-Depth->Greater Than stuff replaces the Glass shader with a transparent shader once the light has bounced 3 times. This makes it so the light doens’t get “caught” inside the object, which would require many transmission and glossy bouces to not result in black spots in the glass.


I don’t have “Greater than” layer on my Blender version (2.90). Is-it an addon?

I tried, but I certainly made something wrong because nothing appears… :grimacing:

Add > Converter > Math

And you use an HDRi as environment lighting.

You do not need to download the largest file. 1k is usually enough to experiment. 2k or 4k for final render.

I tried your idea Ztreem, but I certainly made something wrong because nothing happened… :grimacing:

Greater Than is inside a math node.

You may have to tweak some settings. Look at stuntkoala’s setup.

I tweak I tweak :crazy_face: But nothing like Stuntkoala :exploding_head:

You connected Ray Length to Greater Than. Stuntkoala connected Ray Depth to Greater Than.

Yeah and also it doesn’t work in Eevee - sorry only Cycles. Not sure if you can even achieve such a look in Eevee - certainly not in a physically accurate way.

Ok, I tried again in Cycles and with the right link between “Ray depth to Greater than”, but same result, nothing good :exploding_head:

Share the .blend file here to see what the problem is.

Ok, here is the file :blush: Plexi_question.7z (242.1 KB)

The scene you shared was in the Eevee engine. For Cycles engine you had paused the preview in viewport.
It is also recommended that you use Object > Shade Smooth in the object, along with that two options: the object with good geometry and Subdivision Surface modifier, or “Object Data Properties” tab > Normals > Auto Smooth.
Here the file for Cycles with a free HDRi:
Plexi_question_mod.blend (1.6 MB)

I’m an idiot, I use always Eevee and forgot the process for Cycles… :flushed:
Thank you very much for your help !!! :pray: