smoke dissipation

[ssasumind]

I have a problem here.
I want to create stretching and vortical smoke, like hairlines.
The image file is the WIP sample with opacity AFC settings.
When lines(circles) of the smoke dissipate, they shrink but expand.
I want them to expand and falloff finally.
It looks ok when I increase the buoyancy. But I don`t want the smoke to rise up.
What should I do?

[Rif]

I see you have about 3 choses :


1- read the manual on the smoke dissipation

2- Log in to cgfluids and look in the Tips and Tricks Section explaining exactly dissipation

3- try on simple setups to start with the Dissipation Min value at ~5 and put more strength from 3 to 10 to 20 etc..etc.. and see how it works by yourrself, its pretty much like a switch that turn on a light , when you turn on the switch you can decide whats the intensity of the light shining will be by turning the dimmer nub , well the Light bulb Watts is the Min density , the Strength is the intensity at witch your lighting up the light ( dissipating from 5 'n lower in this example )..

So when the Voxels DEnsity reach the Threshold Minimum of Dissipation min , the amount of strength is apllied in the goal of Bringing this Voxel Smoke To 0 density ..

[ssasumind]

Sorry for the very late reply and thanks for the advice.
I'll try them.

[ssasumind]

I have handled the dissipasion parameters, but couldn't make good results....

http://www.istockphoto.com/file_closeup ... id=4174163
I wanna make smoke like this.

With 'opacity AFC control', it looks good in still image,
but the animation of dissipation is not natural.

[Rif]

hehe.. well for me this looks like a specific method of choice to emit in order to get this result.. maybe FM would help as well ( Texture Mapping Opacity Curve on the Shader that Deforms with the Flow in worldSpace) ..

showing what You did so far and explaining your source ( are you using a Map for emition ? )

"the animation of Dissipation is not natural" : can you show what is it you get ? have you been able to tweak your dissipation on a simple scene first with replicated smoke density sources ? it might take time ( lots of tries) in order to get your dissipating setup to be settle enough but yet do what you want it to do.. You should easily tweak it on lower voxel amount sim to get the numbers perfectly through all your effect length and then uprezing your voxels amount as tweaking low rez and uprezing after should not need much different tweaks on the fluid at high rez only ( not like ALL the parameters in Fluids Land )

AFC Rendering Shader Opacity Cutter ( cause thats basically what it is , a Curve to Control Opacity Level of where the Voxels Density in the Grid are tagged " Smoke Density" ) is not working well in animation ? again if you can show what does it do it would surely be easier to understand whats not working for ya ..

[ssasumind]

thx
here is my sample.
the sample model is confidential of my company. Im sorry that I can't show you the full sample.

as u see, after the swing, remaind smoke dissipation is not natural (shrinking).

Actually I'm using fire, but smoke, for this sample.
But the results are almost same, when I used smoke for the same effect.
I didn't use any maps for emition, temp and fuel.
cuz they weren't helpful for my goal, either.
I just controled it with simple opacity curve.

[Rif]

witch sample ?

[ssasumind]

oops I missed the file...
here u r

[Rif]

Maybe simply Playing with the Low Treshold Higher will cut those Unwanted densitys ?

Without a simple scene to play out with , i dont think i can help much more .. but you got plenty of way of trying this i m sure..

It looks like a Finger Bone On Fire "hellboy " style hehe cool stuffs 8)

hope this help

[ssasumind]

It works! It works! It works! !!!!!
thank u very much!!!!! :lol:

P.S.
We already have four licenses of AfterBurn.
And I'm sure that we'll purchase FumeFX, after some tests with demo Ver.
So we can show you the proof that we purchased AfterBurn, but FumeFX.....
Can I join CGfluids.com?

[Rif]

Yes definitly , Glad it worked , its really hard to troubleshoot without seeing stuffs

You can either send your Info to Kresimir Directly asking him your intention to join Cgfluids and he will contact me or you can send me your serials info to me ( mailto:cgfluids@cgfluids.com ) and i will then give it to Kresimir and he will confirm the legidity and i will add you .. Either way is no biggy .. Register on Cgfluids so i can know your Username to add you ..

Cgfluids is now supporting TP and Fumefx and i m planning to create a new forum for legit Pyrocloster\afterburn professionnal users as well soon ..

Cheers,