[Carrara]smoke and room atmospherics?

[Aunty Betty]

Hi folks, I'm trying to create an appealing atmospheric in a room scene that has the suggestion of areas of cigarette smoke floating in the room rather than just emanating from the cigarette .

What would be the best way to approach this with plausible subtlety?

Would I use alpha images on planes or particles?

Many thanks

[rickei]

I would try volumetric clouds.

set the opacity to low..5%-20% and put the silver lining way up 90%-100%

I would use one big cloud that covers the whole room, and then some small ones spaced around the room to vary the effect(especially around light sources)... I would also put a "thin" cloud at ceiling level as the smoke would be thicker up there.

I actually did some test renders a few weeks ago. I was trying to get a different look, but it turned out looking like a smoky room.
here you can see a clean render and a "smoky" one. It's probably more smoke than you are looking for, but you get the idea

[crazy wabbit]

nice, i wonder if fog would do the trick too?

[Aunty Betty]

Hi rickei thank you so much for your reply. I noticed in your test that the overall effect was to decrease the tonal contrast globally of the image as one might expect from a room where the smoke is evenly spread. What I was hoping to create was that variability you get in a smoky bar where the spread isn't global in the sense that the contrast has a variability to suggest the smoke as a tangible presence.

Do you think this is still achievable with the method you suggest?

[LoneGunman]

I know that you posted this in Carrara section, but did you tried this in Vue (assuming that you have version 6) first ? Vue has considerably better volumetric environment (lights and atmosphere itself) and could be a better tool for this specific problem, volumetric clouds are not too shabby there as well...

[rickei]

The previous ones were not a good example.

you can make the clouds lumpier

when you insert a volumetric cloud, you will be presented with the settings window. there is a preset for "marble", it is what I used for this 2nd set of images, and is a good starting point

I would suggest a LOT of dim little lights in your scene. the smoke plays off of the lights, so you can add lights where you want to see more smoke.

in the 2 renders below, the smoke/cloud settings are exactly the same, the only difference is, I added a light behind the right shoulder of the camera, on the B image.

since it's so dependent on lighting, I cant really share any settings that would help you much. just do a gazillion test renders

[rickei]

I almost forgot. you can use as many clouds as you want, so you can have little clouds in areas where you want more smoke.

also if you have any lighting you should turn the light globe/cone on as it would be visible in a smoky room...there are turbulence settings for the light cone(spot lights)

here's another sloppy test. don't know if it helps or not. I've been working with Carrara's volumetric's a lot lately, for a personal project, and they do leave a lot to be desired. But I'm starting to get some results that I am satisfied with, plus I usually do some fairly heavy post work.

[Aunty Betty]

Thanks indeed Rickei your further tips are much appreciated and certainly have a greater sense of what I was hoping to achieve. Avenues for investigations.

Mr Guman - yes I have Vue but stopped using it a while back simply because of the steep render times. But I certainly have to agree with you with your opinion on Vue's strengths and it's renders can be just stunning indeed.

On a personal level I'd concluded only to use Vue when nothing else could give me that control - but more for landscape work. I'd managed to tweak the render times as best I could in the past with your help as I remember but still wish that render times would be at least 40% faster. I think my last full Vue render was 5 hours after a quality verses speed balance and that's just too heavy when on deadlines. Damned shame. Also it doesn't seem to handle ZBrush GUV cordinates with uv maps so it's a no go for much of my organic work.

[Couerl]

I just used one fog:

[Aunty Betty]

Thanks Couerl - another great tip.

[chrisd]

Also check out Primivol from Inagoni.

[Aunty Betty]

Thanks Chris - I think I've actually got this and too my shame I've never actually played with it. I actually got some pretty funky smoke effects also using some of the 3D enhance c shaders such as vortex in the alpha section on basic spheres.

As I finally created smoke using mapped alphas I did find that some of Carrara's alpha facility seems a little - particularly it's density of shadow compared to it's actual transparency - also it goes whack on a plane object where the plane itself casts a shadow rather than the alpha. hmmm

Is this better in v6 - somehow I doubt it.