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sebrady
09-06-2011, 05:34 AM
I have a glass object IN FRONT of an object with a glow on it. The Glow DOES NOT render. If I dissolve the glass object, then the glow shows up.

How do I get the object to glow when it is BEHIND the glass.

Thanks.

bac9i4mo
09-06-2011, 08:08 AM
sebrady, my recommendation is not to use LW's glow effect. As you noticed it has very poor set of parameters (on/off, intensity and size) and it is fine, because LW is not the tool for 2D postprocessing.
What you need to do is render out a sequence of images in some floatRGB format (HDR, EXR) and load them into some postprocessing app - After Effects, Fusion. And play with glow effects there. You will get results of your tests instantly. In LW, on the other hand, you would be forced to rerender a whole frame to change something on the postprocessing pass.

bac9i4mo
09-06-2011, 09:00 AM
If you still wonder why that glow dissapears behind the glass.. It's because LW applies effects on per-surface level, and each surface stores its index in a special 2D buffer, and glass layer overwrites all surface indices behind it with its own index.

sebrady
09-06-2011, 03:20 PM
thanks guys for all the education, my LW IQ just went way up. Guess I'll render out frames and go to Motion to get what I want.

sebrady
09-06-2011, 05:52 PM
I added a point light in place of glow..........ding ding ding ding, we have a winner. I guess lights render on top of all other layers.

fish for christmas
http://dl.dropbox.com/u/2159257/fish.png

prometheus
09-08-2011, 09:54 AM
I think that a spherical light can give nice glow effects too, next to surfaces..with falloff settings.

Michael