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digitalimagery
10-14-2011, 11:35 AM
I'm building a glass award and followed Robin Wood's tut on glass surfaces which results in a decent glass. I'm curious if any one can offer a tip on

1) how to set this file up so each frame doesn't take 3 hrs 20 mins to render and

2.) which surface attribute contributes to getting the texture map to pop a bit more? You can see in the attached I'm trying it on multiple surface settings but not getting what I want (and probably causing part of the render hit).

I would think a luma matte with the luma punched up.

Also wouldn't mind getting the glass to look a bit more transparent and still hold the refraction qualities.

For those involved in a previous glass discussion with me - we can use the final award image as a test on how to output a matte that will give the same effect comped over a different background as opposed to the one I'm rendering it over.

I had problems getting a decent glass key when output with an alpha in LW.

Thanks a mil. Hoping to launch this over the weekend.
DI

bazsa73
10-14-2011, 12:01 PM
Wire the alpha channel of the text into the transparency channel as subtractive (I guess) which makes the text opaque.

Sensei
10-14-2011, 12:02 PM
1) how to set this file up so each frame doesn't take 3 hrs 20 mins to render and

Use interpolated GI..

Sensei
10-14-2011, 12:05 PM
Let's calculate- 1920 * 1080 * 5 * 100 rays = 1 billion 37 million rays..
without even taking into account reflected or refracted rays..

digitalimagery
10-14-2011, 12:22 PM
Thanks guys. 8 mins/frm for glass I can live with that (by comparison).

Singing in the rain I'm SINGING in the rain.....
DI

Sensei
10-14-2011, 12:26 PM
If you're making animation you should bake GI to cache file, and lock it. Otherwise you might run into flickering problem. Make some test with just couple frames to see whether you see flickering before final rendering.

digitalimagery
10-14-2011, 01:58 PM
I always do a no anti aliasing 10 fps small sized test of the whole thing to check for surprises. In this case I'll render out about a sec of 24fps just to look for flickering. Thanks for the heads up.

DI

toby
10-15-2011, 09:54 PM
Your glass shader settings could be more realistic; biggest problem is that there's no fresnel in your reflection. Google-study "fresnel reflection", it's critical for 3d rendering. Also critical for glass is a good environment to reflect, HDR's are great for that. Specular gloss setting is too dull, if clean, clear glass was the intention. You could save a lot of rendertime by not having any diffuse in it, then it won't render / need any gi, and flicker from Interpolated gi can be very hard to get rid of.

digitalimagery
10-17-2011, 07:55 AM
I'll check this out.

DI