View Full Version : Photorealistic Plastic Shader

08 August 2009, 03:04 PM
I have been working on a project for work and we have ran into a snag of trying to render out a really good looking plastic shader similar to this image. We recieved really good glass and ice but nothing like the image with the contour lines. If anyone knows anything about how going about to achieve this please let me know. We are using Maya 2009.

08 August 2009, 11:20 AM
Why don't you post your results thus far? It will probably help. I'm guessing it is your index of refraction that needs to be tweeked.

08 August 2009, 12:30 PM
To get such a result it's not only the materials that has to be accurate, it depends equally much if not more on your lighting setup. The shaders themselves are simple for such a scene, so spend your time wisely and work more on your lighting. :)

Do post examples of what you have managed to do so far.

/ Magnus

08 August 2009, 03:11 PM
Here is a sample of what I'm getting. This is the closes I've gotten but I'm just not getting that realism I want. This is a phong shader, I've used blinn and mia shaders. My light setup is studio lighting with 2 spotlights using a mental ray area light on them, one point light for the back light and 1 highlight plane. I'm rendering using mental ray with FG.

08 August 2009, 05:35 PM
It seems like your shader isn't transparent enough. Also, perhaps the lighting setup in that studio shot you posted includes a set of black cards to the left and right of the bottle, which may produce the darkness along its edges.

08 August 2009, 06:21 PM
I agree with the other two comments about transparency and lighting. I'd stay away from the phong, because it has a fairly primitive way of calculating specularity/reflectivity. I'd probably use the mia material. If I remember correctly, those dark edges are caused by light refracting as it passes through the material, and it will bend light away from the eye at the certain viewing angles of surface normals. You can probably find online a good index of refraction for clear plastic. As Magnus stated before, lighting is really important and so too are your raytrace settings. You could go as far as getting some caustics on there too to enhance the realism.

Hope this helps!

08 August 2009, 08:02 PM
I feel like the kid who failed epically on the project to "recreate the plastic waterbottle project" in school.

But, regardless, here's what I was able to muster.

This was rough though, I think if you get the geometry down to a T, it'll really help with the refractions. I can't attach the file, but if you think it'll be useful shoot me a PM with your email address.

08 August 2009, 08:18 PM
What about dielectric materials to get the plastic-water refraction interaction? Here's what I achieved with dielectric materials for the water and plastic. My lighting rig needs some adjusting though.

08 August 2009, 11:13 PM
You won't achieve the same result if your borders are much wider than in the example. In the example setup there are gradients just behind the frame borders, which create such an effect in refraction.

08 August 2009, 04:29 PM
Thank you so much for all your comments... I will tackle this shader again and put up my new results.

08 August 2009, 07:36 PM
Here are the new results after making a view adjustments to phix314 shader he so kindly shared with me. Thanks, I feel like its very close but still missing like one thing.

08 August 2009, 01:42 AM
The cap? ;)

But seriously... looks helluvalot better than what I sent you. Well done.

Hmmm... I think it just needs a friend. Some environment tweaks and you should be good to go. One thing I didn't try was on the background's "softbox" having the center be brighter-than white and letting the outside perimiter fall to around .97(v) or so. That, I think, would give the more apparent gradient seen in the photograph.

09 September 2009, 01:27 AM
white line black line

09 September 2009, 10:05 PM
white line black line

Thanks for the link to Glass lighting set-up. Very informative.

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