steam

[itriix]

Hi everyone, i've been studying the pyro tools. I've watched the videos "i can't even count how many times", read the docs, traversed the forums over and over and cannot seem to get steam that looks as beautiful as this (the houdini videos near the bottom of the page) by Mikel Bilbao. I saw his posts in odForce and Sesi and thought it would be a great learning challenge for myself to attempt to recreate that steam. I'm posting my results. It's quite a mess! But it's a start. I'd really like some feedback, if anyone could help locate "what" i'm doing wrong here. I'll give a brief description of my steps and where i'm getting a bit confused:

First off, I can't seem to get those "nice smooth plumes of smoke" that jet out in different areas, mine tends to just turn into a noisey mess. I thought that if I animated the "source velocity" in y, along with the already default x an y noise, that would do the trick, but doesn't seem like it's working out.

Second, if i want the smoke to rise faster, do i raise the "setsourcevelocity" Y velocity? Do I raise the "source object" temperature? Or do I raise the Buoyancy lift? OR do I add a "wind force"? I'm just a bit confused on when and where to be using those particular parameters.

Third, The lighting! I've set up a few spot lights, with deep shadows, but it's still not matching. It's possibly due to the fact that my "smoke" is still too noisey looking and not as smooth flowing.

Well that's it for now, i'm going to keep playing and see what I can come up with. I'd really appreciate any help on this subject.

Thanks,

Jonathan

pyro_steam_8_tk01_x264.mov

Edited November 29, 2009 by itriix

[rbowden]

"play with density values and create several modifiers one for fluffiness and maybe one for edge noise, change the scatter phase to a positive value,light using old school 3 ambient+key+deep shadows, they work great with fluids and are fast! Finally you can render in separate colors ,make the key red for example and the ambient rig blue so you can tweak them separate in post"

That is probably the most important thing about how he created the look of that steam on his website. If you look at the help on pyro about the scattering phase, it has pictures that show you what negative and positive scattering phases look like (which the positive value scattering phase looks similar to his render).

Also, he is basically using RGB on his lights and creating whatever color he wants the smoke (or steam) to be in post. If you did this, it would give you more control of what you want the the steam to look like.

Not much help but hopefully it pushes you in the right direction.

-Ryan

[itriix]

Thanks for the reply Ryan,

A couple notes:

My render does make use of a positive scatter phase and used a couple of modifiers for fluffiness and edge noise *inside of the pyro shader*... It seems to be a game of tug-of-war with the shader parameters. I created a "density field mod" that just shaves off some of the "low density", and then i made a noise mod, which just applies noise to the low density areas. It seems to somewhat work but not completely. I'm still missing something in there i think. I still haven't set up the "lights" to be used in post yet, but I'll do that next. However, I still feel i'm missing something in the "dynamics" side of things. I will just keep tweaking parameters and re-reading the help docs. After I get the dynamics looking good, i'll go back to trying to set up the shader/lights.

I really appreciate you taking the time to respond. I'll definitely be posting my results and hopefully will achieve a similar result soon. I'm thinking there are quite a few people out there that'd be interested in the answers I find

Jonathan

Edited November 29, 2009 by itriix