Translucent plastic isn't translucent?

[Anonymous]

Hi there,

I added translucent plastic to this model to make it look translucent. It doesn't look translucent and I can't find an opacity control.

Any guidance?

Thanks

Luke

[MichaelAubry · Accepted solution]

Hey Luke,

I find the transparent plastic to be easier to work with than the translucent.  Transparent materials have opacity control.  The translucent materials have a translucency value that varies the "scattering" of the light that comes through.  For both settings I recommend just using the Advanced rendering settings.

Best,

Mike

[Anonymous]

Thanks Michael!

[Anonymous]

Hi Luke, I would like to show you a screen shot of a real translucent product that is made at our own place. Designed in Fusion 360. This is a Translucent Acrylic product, made by carefully mixing coloring agents with Acrylic before the Plastic Injection Process. By using special photographic technique and lighting that shot lights at a certain angle from the top; Part of the translucent body became near transparent. Please look at the small tube with the flower stem. Translucent products in real world really depended on the scattering of light. But I had found that the Translucent Appearance from Fusion 360 is not really translucent. I tried to move the light source to different angle, and still could not get the proper translucent effect.  Mike, I think that part should be improved. Maybe the picture that I attached here could be a good sample for your team.

[Anonymous]

Thanks Kingson!

[TrippyLighting]

Transparent materials attenuate light. Filters are transparent as they attenuate specific light spectra.

Translucent materials scatter light internaly and attenuate light in the process. The proper term the CG world is called subsurface scattering.

[cekuhnen]

translucent is mainly used for thin paper like materials
while sss is used for volumes

Trippy how is that in Indigo?

[milos.hasan]

Hi all,

"translucent" in Fusion 360 means precisely "subsurface scattering". The former was chosen as user-friendlier by user interface folks. Moreover, "translucent depth" means precisely "mean free path", i.e. the average distance between light scattering events.

If the effect is not translucent enough, try increasing the mean free path (a.k.a. translucent depth). For extra effect, make the depth decrease from red to green to blue (which commonly happens in nature). Also, make the color reasonably bright (technically, the "albedo" should be high to cause a strong glow effect), and make sure your model has real world units. Here's an example where it's done correctly.

The "transparent" material has absorption but no scattering. It can be used for clearer, colored glass or plastic. The paper example would correctly require a different material model meant for diffuse-ish transmission through thin shells, which does not exist in Fusion yet. Using the current translucent may give OK results though.

Milos

[TrippyLighting]

Interesting. I was going to ay somthing similar in respect to the question referencing Indigo Renderer.

Usually a subsufface scattering material in Indigo has surface properties such as reflectance and refraction. It also has to have a medium that describes what to do with the light once its refracted from the surface into the material. Often the Henyey-Greenstein phase function is used to describe the scattering properties.

That works best for objets that have a certain thickness such as the orange Vase in one of the posts above.

For thin materials such as paper or curtains Indigo uses a diffuse transmitter as an approximation. However, as described that isnot yeyt implemented in Fusion as it only requires a surface model without volume. In Indigo there is also a Double-sided Thin material that is often used to simulate leafes and plant foliage ans that has two differnt surfaces, with the top being more specular reflective and hte bottom more diffuse.

[cekuhnen]

Also as Michael mentioned if you want to work with materials you really have to use the advanced render mode. there is a significant difference in how materials are rendered!

[KarlSchmidt]

Yep. Currently the normal and quick modes entirely disable the translucent effect. A brief summary of the quality mode differences is:

Advanced: All the bells and whistles on.

Normal: No translucency, simplified reflections and refractions for rough materials.

Quick: No translucency, simplified reflections and refractions, simplified lighting and shadows.

In this case translucent seems like the right type for the flute, but you'll need to render in advanced mode to see the effect.

[Anonymous]

Running into this problem again. Can't change transparent plastic opacity. Translucent gives an opaque material. I have a part that shows about 50% opacity at about 1mm depth. The part is white.

[KarlSchmidt]

Testing locally I get

This is not to say that there isn't something else going wrong, but I think the feature works in general.

Was this a cloud, local or in-canvas rendering?

Cloud and local renders using the render button (teapo) should always have translucency enabled.

If it's in-canvas in the Render workspace then you need to make sure that the "in-canvas render settings" (cog) are set to advanced and that you have enabled the renderer (sphere with an arrow).

For the material, you might want to double check that translucency is enabled and that the depth is a sane amount for your model. Translucency doesn't work well on features that are significantly smaller or larger than the depth. If you have a 1km object and set the depth to 1mm then you wont see any difference from enabling translucency. If you have a 1mm object and set the depth to 1km then it'll just look wrong in some unpredictable way. Your 1mm translucency depth should generally be well-behaved for a Fusion model, though.

[TrippyLighting]

Help is always welcome, but you do realize that you are responding to an ancient thread ?

[Anonymous]

Thanks.  My install was complaining about the video driver so earlier I was encouraged by the interface in a banner at the top to knock down some of the rendering "bells & whistles" and it's likely that in my case, this is why it's showing the way it is on mine.

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@cekuhnen wrote:
Also as Michael mentioned if you want to work with materials you really have to use the advanced render mode. there is a significant difference in how materials are rendered!

---

[KarlSchmidt]

Well, the thread is ancient but I was specifically replying to a question asked in it four hours ago 🙂

[TrippyLighting]

Oops 😉

[Anonymous]

Ah yes, the old "resurrect a thread" vs "don't start another topic" conundrum. 🙂

Here is the part in question. It is an audio jack.

Translucency depth is very low, 0.030mm. Can't see the pins. Actual part is white and you can see the pins as if the material were 50% opacity and white.

Translucency depth is very high. Makes the part dark.

Transparent white produces a colorless clear part... like glass or acrylic. 

Reducing absorption distance just makes it dark

So the question is, how do you get a white part that is 50% transparent?

[Anonymous]

I thought about the problem and realized it may be a question of surface finish and not a transparency. Tried frosted glass and its pretty darn close.

[vector29]

Luke,

I took a crack at getting F360 to render something resembling your photo of the audio plug (cloud render at 'final' quality). Please excuse the quick and dirty modeling I used for the gold leads.

I agree with the earlier answer that a transparent material will work better than a translucent material for this particular visual appearance. I started by creating a copy of the "Acrylic (Clear)" texture and adding some roughness (0.30). I also increased the absorption distance to 20 mm, which is just a bit deeper than the thickness of my model (16 mm). As you noted, smaller distances lead to too much absorption in the interior of the model (making it too dark).

The result looks pretty good to me. If you want a more accurate surface texture match to that 'molded' look in the original part, you can add a texture map image using the "Relief Pattern (Bump)" option (this option is hiding in the 'advanced' section in the material editor).

--thanks, Ed