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View Full Version : Dry Ice/Smoke Help Please!!


shirak23
04-03-2007, 05:03 AM
Okay,
I'm trying to make a dry ice effect, foggy smoke, you get the idea. I've got the creation of particles fine, that's not the problem (at least not really). I'm having a serious problem getting it to LOOK like dry ice. I've followed some texture tutorials for smoke, but not only does it look like garbage, it's too dark.

As you can see, in the second pic some of the particles render completely black (this is using Vray). Any ideas, why? I've read that the scanline renderer is better for particles than Vray, but I thought Vray 1.5 now supports quality particle rendering, so I don't know...

1) Can anyone help me with the look: white, wispy dry ice/fog?
2) I've got the particles coming out of an open box (a stand in for a microwave, don't ask) and I've got an omni light inside. I want the dry ice to be illuminated by this light so that it "glows" a bit.

I haven't tried Afterburn yet, but I'm going to, so if anyone has Afterburn advice/tips/help that would be awesome too!

Here are some pics of what I've gotten. Yuck.

Oh yeah, I'm using between 800,000 and 1,000,000 particles...

Thanks.

depleteD
04-03-2007, 04:42 PM
My best advice is have some video refrence.

What u wanna do is have it sink, not rise,

To get the look I would use afterburn and play with the noise and density values.
Also have turbulence, use 3 wind spacewarps have like a large noise pattern, medium and small one.

but USE REFRENCE :P

As for lighting you will want to use afterburn. You can get the selfshadowing you want that dry ice gives itself.
With afterburn use a small number of particles. Let the shader do the work

Hope this helps

muzbee3d
04-03-2007, 05:06 PM
This will likely get you where you need to go.
read it and just play with the mAx file http://forums.cgsociety.org/images/icons/icon7.gif

http://www.creativecow.net/show.php?page=/articles/yousefi_morteza/cow_clouds/index.html

PsychoSilence
04-03-2007, 05:27 PM
fume would be perfect for the job...unfortunately you donīt seem to have it :(

at least hereīs some reference on dry ice/liquid nitrogen :) :

http://youtube.com/watch?v=95Gk4fprseg

maybe i can come up with some assembly file...

kind regards

anselm

EDIT: i attached a very quick and dirty superspray approach. maybe it can give you a hint...

mackdadd
04-03-2007, 05:40 PM
http://www.the3dstudio.com/product_details.aspx?id_product=2600

that's some great particle smoke.
check out allan mckay's website, too. search him, he's easy to find.

BrandonD
04-03-2007, 08:04 PM
You're using way too many particles, dude. Yes, Fume would be great for this kind of effect. I did something similar for that lame "Dracula 2000" film years ago with Particle Studio and Afterburn. You don't need either though. Using opacity mapped facing particles is a good start, though it may make it difficult to do quality illumination of a faked volume of particles. That's where volumetrics like ABurn would be good. The trick is that dry ice is heavier than air, so it sinks and crawls on the ground.

Square polygons mapped with a radial gradient have always been good for soft vaporous effects. When illumination becomes an issue, sometimes it's helpful to give those cards some depth, so I make a Grid, add two Bend modifier to shape the object into a semi rounded shape, then collapse it. Use ShapeInstance to put these on the particles and use a semi-self-illuminated material with an opacity mask (Radial Gradient masked by a Particle Age map). You can put a ShapeFacing above the ShapeInstance to force the orientation of the cards to be towards the camera. Don't try to raytrace shadows through this at all! When you get a bunch of these clumped together with the right opacity settings, it starts to look like vapor. The extra flex to the cards lets light catch them better.

PsychoSilence
04-03-2007, 08:35 PM
thanks for the rich input brandon!

yeah, i guess a pflow solution would be way better and more open compared to my one-minute-superspray-"fountain" :D

Nice trick with the bended shapes!

kind regards
anselm

shirak23
04-16-2007, 12:30 AM
Hey all,
I just wanted to say thanks for all the input! I've been so busy that I haven't had a chance to reply or work on this project, but I'm going to work on it tonight. As soon as I have something that's looking a little better, I'll post it.

Again thanks for all the assistance and interest!

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