View Full Version : Particles: Premultiplied?

12 December 2002, 07:04 PM
Im having a tough time rendering out a particle seq for combustion. When I do and import that render seq into another comp package the render the particles look like crap. I have tried a ton of way to render out the particles, and they still look crappy. The particles look good when they are slapped on what ever image you are comping to, but when you put the particles to their own transparent layer it looks crappy.

Any help would be appreciated.

Geoff Richardson - Visual Effects Artist

Vancouver Work# 604-602-2608 Ext #2608
Email --

12 December 2002, 07:23 PM

i have seen this as well....

When you create a solid, ensure the settings are not transparent... there iseems to be something to do with the alpha of the solid affecting the particles...

so if you apply your particles to an opaque solid then when you render the particles as an image sequence then you should be fine....

Just use the "Screen" transfer mode or a luma key to get rid of the black areas.....


12 December 2002, 07:23 AM
Good idea about using the screen mode, but if you are using a smoke that wont work. You will lose all blacks in the smoke.

12 December 2002, 01:51 AM
to do this with smoke copy and paste the smoke layer and make the smoke particles of one layer white, then use this layer as a stencil layer for the other based on lumanince.

Milo FX
12 December 2002, 04:00 AM
After several problems with Combustion particul generator, I returned to use Illusion for particul tasks. When Discreet announced that they purchaised the codes of Illusion, I was thinking that I will be create the particuls in Combustion workspace as fast as in Illusion. But it will not... I think Combustion makes the same probleme as Illusion vers 1. In that version when you render the particuls without background with alpha channel, it makes a black crispy areas around the particuls. But in vers 2 they dissolved the problem. And now, when I have to use the particuls, I go to Illusion with my background layer, I edit the controls (all previz are real time) and I render them without background with alpha channel, than I return to Combustion and I simply composite them over the background...:thumbsup:

12 December 2002, 11:48 AM
So this error was carried across from illusion to combustion?

I will email combustion support... maybe they will find this info useful....


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