Light Smoke Rendering

[CG_Utopian]

Hi,

Is there any way to get rid of the graininess in the smoke generated with the "Cigarette Smoke" preset? i am trying to simulate a grill smoke for a very high resolution rendering/print (20,000 px) and i really need to make this grain in the smoke less visible.

Is it possible to render the result from "Cigarette Smoke" preset, as a normal smoke, not particles without affecting the look of course?

PS. I am very very new to Phoenix FD

Much appreciated

[Svetlin.Nikolov]

Hey,

Not 100% sure about the issue, so I'd guess a few solutions - you can increase the particle number in the source, so you'll have less individual particles visible in rendering. You could additionally change the Particle Shader mode from Point to Fog and it will render using the fire/smoke grid shader, but this will decrease the detail or increase the render times, so I suggest keeping the Point mode and simulating more particles. If you don't want to simulate again, you could increase the count multiplier on the Particle Shader as well.

Cheers!

[CG_Utopian]

i already tried to increase the particles count but the look of the smoke was completely changed, in the image below you can see what i mean by the "graininess" .. the look and the density is almost exactly what i want, i just want to make it look smoother and without the grain.

and it there a way to control the transparency of the smoke generated from "Cigarette Smoke" preset?

BTW thanks for the quick reply

[Svetlin.Nikolov]

More particles, that's the trick with this kind of effect Check the count multiplier, and the Fog mode - either one could take it in the right direction. You can control the size, opacity and shadow strength of the points from the Particle Shader - check the Point rollout. Maybe if you increase the size a bit and reduce the opacity, + count multiplier, this would also help.

Cheers!

[CG_Utopian]

ok, I'll try that, thanks a lot.

[CG_Utopian]

I increased the count multiplier and adjusted the point alpha, it partially solved the problem when rendering around 1000 px. but when i increased the resolution of the rendering to around 10,000 px, the smoke less visible and much more grainy, so i increased the multiplier more, but it seems there's that it's not possible to increase it enough before 3ds Max crashes due to RAM shortage, and i have 120 gb RAM on my machine.

Is this method (rendering smoke with foam/points) not suitable for high res renderings? or am i still doing something wrong?

[georgi.zhekov]

This is the right method, unfortunately the more particles you have the more ram they will need.

Nevertheless it shouldn't crash when you run out of memory. Can you send the scene over to support@chaosgroup.com so we can check it out.

[CG_Utopian]

Of course, i will send it to you in a moment and i will include the link of this thread in the email.

[Ivaylo Katev]

the task seems really hard, my personal experiments show that you need about 50M particles for only 1k image, for 10k you need 100 times bigger cont, because it has 100 times bigger surface. this is incredible number 5G particles, if i'm not wrong, phoenix is limited to 2G particles.
i think you have to seek a compositing solution, i mean render multiple times with low particle count with different seed of the multiplier, and then combine them in post. as i remember phoenix has no seed of the multiplier, but perhaps the multiplier value can be used as seed itself, not sure.

[CG_Utopian]

In the image below you can see the rapid increase in memory consumption during the "Multiply Particle Count" phase.

I am using phoenix FD 3.0 and Vray 3.40.03

[CG_Utopian]

I see, thanks for the explanation. The scene has been sent to the support anyway.

But still wondering if there's a more efficient way that i am not aware of as i am new to phoenix FD, to get the result i was looking for. which leads me to the next point, Phoenix FD suffers of huge lack of learning materials online, would love if you guys could address that.

Tnaks

[Svetlin.Nikolov]

Already working on it

[georgi.zhekov]

We reproduced the crash, now we need to fix it

Thank you,

[George Barzinski]

The problem is already fixed.

Thank you for this report.