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BigHache
06-17-2014, 11:57 AM
I feel like I should know this but I'm not finding a good solution. What's a simple way to make a diffused transparent surface? For something like vellum or a clear rubber material.

spherical
06-17-2014, 03:30 PM
Depends upon the goal, really. Refraction Blur in the Dielectric material can give you one effect. Surface bump can give another. SSS materials can have elevated transparency. I'll go check on some other stuff.

Tested Dielectric with Refraction Blur
Tested Sigma (doesn't have Refraction Blur)
Tested Sigma2, with and without Refraction Blur

All different, all good in their own way. 1st image is Sigma with 3" Distance on a 6" cube and Turbulence on the Bump channel.
2nd image is Dielectric with 5% Roughness, Refraction Blur, Interpolated, Sample Size = 0.5, Blend Size = 10.
122428 122429

BigHache
06-17-2014, 03:59 PM
I've done surface bump before and it can work for some situations. I've not messed with the SSS materials at all but that might be a good direction.

spherical
06-17-2014, 04:15 PM
Just uploaded a pair of tests.

BigHache
06-18-2014, 04:10 AM
Depends upon the goal, really.

True. This is close to what I'm trying to achieve.

122436

The Dielectric effect isn't there. The material is too clear. The Sigma is better but it's still not quite what I'm after.

I'll keep playing. Thanks.

JoePoe
06-18-2014, 01:57 PM
I took Sigma2 out for a spin. It has a transparency setting so....
Also, I used a weight map to differentiate the top loop from the sides so they could get slightly different treatment without a completely hard edge.

the checkerboard "in" the object is refraction of the floor behind... not reflection, which is practically zero on the sides.

122438

spherical
06-18-2014, 03:28 PM
The Dielectric effect isn't there. The material is too clear. The Sigma is better but it's still not quite what I'm after.

Try a combination of the two using Material Mixer in db+w Tools (http://www.db-w.com/products/dbwtools/docs).

Also may be related to IOR in Sigma or Sigma2. Try higher or lower to see how it changes the transmission in combination with transparency and depth variations. One of the SSS materials should be able to get this but the Mixer really should be able to do it if not.

BigHache
06-18-2014, 03:38 PM
Thanks guys. I wound up using what I have for the moment (which I'm not satisfied with just yet) but I'm not working on this project again until tomorrow or next week. More testing to be done!

BigHache
06-19-2014, 03:47 PM
OK the Sigma2 node is not bad and I think will be sufficient for this application.

122465

I tried DP Kit Material Mixer with Sigma2 and Dielectric and it basically only gave me the A input. So I'm not sure if that was just user error or those particular nodes don't play with Material Mixer.

Thanks again for the help!

spherical
06-19-2014, 11:43 PM
Looks good. I'll take a look at Material Mixer with those nodes. Never had an issue with it. Can you post the network?