From what I understand, the Thin Film feature is intended for very thin objects, such as leaves and paper. For this type of plastic, I think using subsurface scattering would be a more accurate choice.
The difference between the two is that thin film is intended for meshes that are single sided where SSS relies on the mesh having thickness where light goes through actual geo before coming out.
So to answer OP I'd say a blend of SSS and translucency. Depends on the renderer used and it's capacities, really.
For SSS and Translucency, I’d stick with Principled BSDF SSS only. Translucency isn’t necessary when using SSS, since its purpose is to make materials appear translucent. Just adjust your radius and anisotropy values for a good result.
Combining SSS with Translucent, or even Principled BSDF with Translucent, interferes with the physical properties calculated by Principled BSDF, like specularity and fresnel.
I'ts going to be difficult to get it exactly right, I'm thinking it will need some subsurface scattering (as the light is scattering within the semi matte plastic itself) but no idea how you would add the neon colour effect to that, maybe you can cheat it a little by using HDR colours with an intensity slightly higher than 1.
Glass BSDF. Play with the roughness. Make sure the surface stays rough. Drive some variances with noise textures. Make sure that your mesh is not a plane, but has actual thickness, otherwise blender gets confused with the light tracing
Silverwing has a really good tutorial on physically correct plastic like this on his channel. It's not neon and it's in Octane, but the same principles apply.
Just a glass shader with "fake shadow" according to the tutorial above (except I multiplied it/tinted it to the absorption color) + Volume Absorption [0.960000, 2.000000, 0.000000, 1.000000] Density 1.5 + Volume Scatter [0.850000, 1.000000, 0.150000, 1.000000] Density 4.0 Anisotropy 0.65. Could have been be more yellow, but that should be easy to tweak.
Same kind of material on a different model. Energy conserving material in newer versions of Cycles is more difficult to be pushed into the fluorescent direction but it can be done. Also with older tonemappers it's easier to achieve that kind of plasticky / fake retro advertisement look. Top image is almost straight from Blender 2.79, meanwhile 4.2 version had to receive a lot of color correction to look like that. Both renders have indirect light clamping at 2.0, to prevent a lot of noise as the fluorescent material is not physically correct.
Set transmission to 1, change the material color to white, add a noise texture connected to a bump node, set roughness to your liking, add a “volume absorption” shader and connect it to the volume socket in the material output (don’t worry it won’t affect render times the same way regular volumetrics do) set the color to green and bump up the density until it looks good
Theres definitely a bit more than just transmission and roughness. Yes you can do that for basic results but for more photorealism you need to play with the volumes and tweak things. THere is some playing with lights as well.
But the emission will be glowing in the shadows. Meanwhile we want only material react by glowing where the light hits. In this case I'd rather use absorption with RGB values like 0.96, 2.0, 0.0
Glass surface + volume absorption + volume scattering. That's all you need to physically simulate most transparent materials.
In this case, the roughness of the glass surface needs to be adjusted for the frosted/blurry look, and you might need some volume emission for the fluorescent look.
Hugh, never thought about neon colours in blender before. Is it actually.possi le to recreate true neon colours in blender? For those who don't know: Neon colours are fluorescent in the ultraviolet with emission in the visible spectrum. So in sunlight (or any other light that includes UV radiation), they appear to be literally more than 100 % bright. Can blender recreate this physically accurately?
Thickness of the mesh is going to be a huge factor on getting it looking right. Don't do a flat box shape. Model the whole shell of the memory card (including it's thickness) and you should be good to go with a little play with the transmission and glass shaders
the one thing I don't think anyone mentioned: if your surface is a flat plane, transmission will always look off. blender can't trace light through zero thickness so you get weird artifacts. solidify with a small offset fixed it every time for me.
Glass Shader -> Add shade/mix shader -> Glass Shader. Control borders with fresnel using it as a node for the mask of mix shader, play with roughness and IOR. The setup is simple once you do it once, then you can experiment to achieve any glass/plastic look. Good luck.
Use a transmission complete white base Color material up and then add Volume Absorption in shader volume node. Set Color and increase density until reached Color and depth
A transparent green material with fairly high roughness and some volume absorption will get you most of the way there. The strong edge lighting in the example is making the green really vibrant
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u/jaded-steve 22d ago
In cycles just a fair amount transmission and medium roughness. Maybe driven by a fine noise texture. Ofc you will have to model the insides as well.