View Full Version : Final Gather/Primary Visibility

03 March 2007, 02:47 PM

I want to light a scene using only FG, therefore no classical lights. The light source would be a sphere with a ramp mapped to the incand-slot. That ramp also should be visible in the background. I also would like to use a sphere INSIDE that sphere with an image mapped to the color-channel for reflections.

I set the outside sphere with the ramp to primary-visibility = on, visible in reflections = off and the inside sphere to primary-vis = off, visible in reflections = on.

Sounds right to me, but the reflections do not show up. I also don't want to map an image to the reflection-color-slot because I am using a DGS material.

Thank you,

03 March 2007, 03:15 PM
if you're using the dgs material, why don't you just go under the shading group, go to environmental shader, create a spherical environment and then map your image, that way your dgs will reflect without maya trying to calculate the extra geometry. I would also use the IBL node for your big sphere and place your ramp into the texture attribute. Once again, it's just faster.

On the other note, are you using nurbs or polys for your spheres, if poly's make sure your normals are pointed inward.

03 March 2007, 05:29 PM
actually you need the exact opposite,
you see any object(your smaller sphere) in a scene that has FG flags on even when prim visibility off will "block" light from an indirect light source/bounce(your big sphere in this case) meaning you will get a black render(unless you have enable default light enabled in render globals, you might want to turn that off by the way)
what you want to do is have the smaller sphere emit fg(or just use camera background color..same thing) and without visible in reflections, then the bigger sphere with visible in reflections and the rest are off.

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03 March 2007, 05:29 PM
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