need help with flame, smoke

[Toiletfreak]

combustion, good particle system, fully customizableless then 2k( i think)

[thomaspecht]

the particle system that comes with combustion is also being sold separately: http://www.wondertouch.com/

should be alot cheaper than getting combustion - unless you need compositing functionality anyway.

[sundialsvc4]

Flame and smoke are usually done with particle-systems. I don't know if the package you are using includes them or not. I've also heard of studios that literally built a campfire and filmed it.

Both "smoke" and "flame" are very random effects, in nature, which work best when they look quite un-predictable. A good way to get them is to composite the basic effect on top of itself several times, using translucent layers, slightly offsetting the time. The final effect for smoke should remain translucent while fire should wind up, if not completely-solid, very-close.

Smoke consists of two parts: (1) the smoke, and (2) "smokiness."

Smokiness, as in a late-night bar, is much easier to achieve because it is simply a layer of general, colored, "translucency." To this is added a top-layer of slightly more detail to give direction or shape to the smoke coming from the source.

Fire, also, consists of (1) the fire itself; and (2) the light it casts. And in the case of fire you look at the light much more than the fire. From a CG point of view, the light doesn't actually come from the fire.

The qualities of that light are extremely important. You want that fire to cast a general flickering light over everything (and you also must have a flickering catchlight in characters' eyes). But if you try to achieve that flicker in the usual way by putting lots of spot lights here and there, in order to capture the effect at the same time you're rendering everything else, you watch your render-times plummet into the tank. The light of a fire is an "additive effect," so generate it separately and composite it in, tweaking as you see fit.

What you do is to render a handful of "light-only" layers, each layer coming from a different lamp, perhaps none actually positioned right where the fire is. The light comes from behind the camera and reflects right back into it. Mask off anything you don't want to get light from a particular lamp. Things that are to be illuminated need to be in there but for "shadows only." Now composite those layers right-on over the top of everything, randomly adjusting the intensity of each. They can be very short clips, combined essentially at random. The effect will look right and it's easy to do; much easier and faster than trying to rig and adjust lamps "in the scene."

Catchlights in the eyes, if you need them, are also a single composite layer from a point light source. Oddly enough, it really doesn't need to flicker.

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