View Full Version : volumetric lights

08 August 2005, 01:08 PM
Hi, I have a orange/yellow volumetric spotlight in a scene, emitting light using a projection image. The plane behind this light is white and unless I put the opacity of the volumetrics up the light is virtually invisible. Unfortunately increasing the opacity creates dark grey projections around the outside of the light in the renders. Has anyone else had this problem or know how to correct it?


08 August 2005, 11:18 PM
Have a play withe all the settings.
Its probably the best way to figure it out. Upping the opacity and maybe decreasing the attentuation, or fiddling with the effect dissolve. Change the density... experimentation is the key.
And it also depends on what you are trying to create...
Maybe a volumetric light isnt what you are after, maybe you could combine it with Hypervoxels.

08 August 2005, 12:31 PM
Thanks for the response, I have had a pretty intensive mess around with the settings but unfortunately I either lose the effect of the light over the white background with low opacity, or the dark fringes show up with higher opacity. I read in the manual that high opacity causes objects behind to blend into the effect (in this case a white plane) and I was hoping there might be a way to stop the blending. I'm not sure where the dark colour is coming from though - the light is amber. I will try to post a picture of the problem once this post is cleared and i'm allowed... basically its a projection of a hologram - similar to the one from r2d2 in starwars, but in this case the projection is an extruded logo.

The rays shoot out matching the text of the logo - achieved with the light projection image. this image is black and white. maybe that's where the black is coming from? - but i don't know how else to stop the light. maybe I will have to place a clip mapped plane infront of the light instead???

08 August 2005, 02:51 AM
You could try upping the volumetric light antialiasing also, I found when working on the pic in my sig, the antialiasing has a huge effect on a complex light (such as the one I use shining through venetian blinds).

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08 August 2005, 02:51 AM
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