Passes

Eugen Fetsch · August 26, 2018, 12:53:20 AM

Is it possible to integrate the pass for scattering medium?

A "UV Pass" would be great too!

Rex · August 29, 2018, 09:56:24 PM

Hi Eugen,

What are the results you expect to achieve with a "scatter pass"? Can you provide an example of what this would look like?

Eugen Fetsch · August 30, 2018, 07:24:41 AM

Hi Rex,

actually I don't really know if it's even possible to create such a pass. $:-\$

I've thought to use one of the available passes for denoising + final color adjustment in the compositor and couldn't find a pass that is useful. That's why I've asked.

The AO and Diffuse passes are empty. The Clown Pass, Shadow Pass and Depth Pass show the base geometry (cube).

Rex · August 30, 2018, 08:26:39 AM

Good points. I definitely see the benefit. Maybe we can detect areas outside of a vdb with 0 density to at least have the correct silhouette.

I'll inquire with dev to see what's possible.

Thank you

Eugen Fetsch · August 30, 2018, 09:38:04 AM

Sounds like a plan

Thanks!

bdesign · September 04, 2018, 07:57:31 PM

Hi Eugen-

You can create your own Scattering Medium pass with the following procedure:

1. Set the Scattering Medium Transmission and Albedo to black.
2. Set the Environment Background Color to white, and turn off Ground Shadows.
3. Render image and then invert.

The example images below are quick renders at 64 samples each. They are:

1. Bunny VDB beauty render.
2. Bunny VDB mask render.
3. Bunny VDB mask render inverted in Photoshop.
4. Result of mask used as Layer Mask with a Hue/Saturation Adjustment Layer applied to Bunny render.
5. Smoke VDB beauty render.
6. Smoke VDB mask render.
7. Smoke VDB mask render inverted in Photoshop.
8. Result of mask used as Layer Mask with a Hue/Saturation Adjustment Layer applied to Smoke render.
9. Result of mask used as Layer Mask with a Gradient Map Adjustment Layer and a Hue/Saturation Adjustment Layer applied to Smoke render (also used to mask out and change the background).

Hope this helps

Cheers,
Eric

Eugen Fetsch · September 05, 2018, 01:20:58 AM

This is a good workaround till the pass is implemented. Thank you.

DMerz III · October 01, 2018, 09:03:49 AM

Eric, you're the champion of solving puzzles. Thanks for sharing your wisdom once again

bdesign · October 01, 2018, 04:40:16 PM

Quote from: DMerz III on October 01, 2018, 09:03:49 AM
Eric, you're the champion of solving puzzles. Thanks for sharing your wisdom once again

Aww, man, you're too kind, David

Thank you!

Cheers,
Eric