OTOY Forums

Hi there. I have a question about using medium to make fog .. and god rays.

Reffering this question to google just comes up with articles for Cinema 4D which is of no use to me. I'm using the Octane 4 plugin for DAZ.

So my problem stems from the fact that I understand that to use medium you have density settings .. but then you need to choose between scattering or the other one .. begin's with an 'A' (It's not in front of me right now but I can pronounce it anyways). There's little to no help at all to understand how to use this to generate a fog. I'm just trying to have a room feel a little smokey with some nice diffused light rays .. but so far all I have is a dark black look .. that still doesn't resemble fog .. or a greyish thing that just looks like I put a near transparent layer over the image in photoshop.
None of this looks like fog.

Yes I realize one needs to choose the right density .. scattering colour and intensity .. and that the lights in the scene play a role. But there's no help to tell me where the baseline is.

For instance .. Medium is pretty much off if set to density of 1 .. but I found that even going up to 1.5 make things too dark ... but the scale goes up to like 10,000 ... when in the hell of it would I use that much. And how / why would i use scattering .. and the other one .. in which circumstances do I need one or the other .. or both?

Can we not just have a slider that says "fog intensity"? .. Yeah I know that's dumbing it down .. but again .. no reference material to know how to use it .. and so far all my attempts at fog have looked f**king awful.
Would very much appreciate some help to understand how this should work and what might be a reccomended baseline setting for creating a nice bladerunner-esque fog .. and a lightly smokey room.

Thanks,
Sparkie

Try using the Environment Medium with a large radius. The technique used in other 3d apps where you use a Volume Light will not work with the DAZStudio plugin, because it does not support Volume geometry (ie. VDB files).

Paul

face_off wrote:Try using the Environment Medium with a large radius. The technique used in other 3d apps where you use a Volume Light will not work with the DAZStudio plugin, because it does not support Volume geometry (ie. VDB files).

Paul

Is the support planned for any future version or is it off the table?

Support for VDB geometry is not currently planned for a future release.

Paul

happy new year !

i'm still struggling with environmental volumetric fog.
here is a scene (rendered at 6000 samples): as you can see, the fog is very grainy.

here are the environment settings: and the general settings how do i get a better looking fog ?

i'm still struggling with environmental volumetric fog.
here is a scene (rendered at 6000 samples):

I'm not sure sorry - however trying tweaking the scattering and absorption colors - and you may need to increase the light emitter power too.

Paul

still fiddling with the fog.
question about mesh lights in general and with volumetric fog:
i'm using primitive planes with only 1 division (and of 1 meter side).
How does the number of divisions affect the texture emission ?
Should i have more divisions ? And/or a bigger primitve ?

cyprine wrote:still fiddling with the fog.
question about mesh lights in general and with volumetric fog:
i'm using primitive planes with only 1 division (and of 1 meter side).
How does the number of divisions affect the texture emission ?
Should i have more divisions ? And/or a bigger primitve ?

I think the fewer polygons the better, but this was based on old versions of Octane - so you might get a more accurate answer if you post this question in the general Octane forum.

Paul

Hello, there is a way to drive medium density through a noise node, so that the fog scattering can be less even? Or isn't currently supported?

Hello, there is a way to drive medium density through a noise node, so that the fog scattering can be less even? Or isn't currently supported?

I'm not sure if this will work - but you can try it for yourself to find out.

Paul