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Hello,

I would like to add some atmosphere to the background of my renders. I figure I could use a Depth pass for this or a fog environment. Let's start with the depth pass however.

In Blender there is something called a Mist Pass that is pretty cool. It is like a depth pass with some options. Not sure if there is something like that in Octane. In any case, how does one do a depth pass or Z depth pass in Octane. There are some tutorials on YouTube but they seem to be out of date because it does not look the same.

Thank you.

Best,

Joe.

Hi Joe,
you can use the Z-Depth pass in an AOV Group, to simulate a fast fog effect.
In this case I have use it to mask an Opacity pass (White), adding some coloring, and an Overlay blending mode: ciao,
Beppe

Hello,

On top of beppe's suggestion, if you are interested to try via actual volumes, may be this could help: https://www.elsksa.me/scientia/cgi-offl ... er-volumes

Since my website is mainly covering Octane Standalone (core), here is the official documentation for Octane Cinema 4D: https://docs.otoy.com/cinema4d//Fog.html

First of all, thanks to both of you.

To Beppe: I have never used AOV passes, just used the beauty pass. I never tried any of the compositing nodes in Octane that you are using in your setup there. I didn't know that Octane did compositing. Looks interesting.

Suppose I want to invoke the depth pass, where do I start? How to invoke one of the AOVs? There are some tutorials on YouTube, but I think they use an old workflow that is no longer pertinent. Maybe I should start with the manual.

Edit: Unfortunately the manual seems out of date. Is there a tutorial or website that explains the new AOV workflow clearly and concisely? While I have rendered a lot of things with Octane, I never rendered passes (and for now am really just interested in a simple Z depth pass). Beppe, your image looks amazing, and I would like to understand it, but I don't really know what is going on. If you you can give me four or five steps to how to make a Z depth pass that I suppose I would use in After Effects, that would be great (although I am really interested in the compositing workflow).

To elska: Thank you so much! Your information about volumes looks really cool! As soon as I get this depth pass and AOVs worked out, I will certainly dig into that! Looking forward.

Thank you!


I have another question, but I will ask in another thread because it is unrelated.

Ok, le's try with this example: 1. Go to Render Settings/OctaneRender/Render AOV Group, activate the Enable checkbox, and press Add render AOV, then info/Z-depth AOV: 2. Correct the Z-depth Max value, checking the result in Live View: 3. Go to Render Settings/OctaneRender/AOV Groups, and press Add input button: 4. We need the base layer for compositing, so, in the Input 1 node, press the All layer button, then Render AOV output/Beauty: 5. Then we need a White pass to mimic the fog on top of the beauty, so press again the All layer button, then choose Render AOV output/Info/Opacity: 6. Press the Node Editor button: 7. In the Node Editor, extract the Mask pin from the Opacity layer, and choose Render AOV output: 8. And choose as Input type the Z-depth AOV: 9. Finally select the Composite AOV node, and change the Alpha operation to Alpha compositing, you can continue to fine toon the Z-depth Max value, checking the result in Live View: You can also use the Scale, Color Multiplier, Opacity, and Bland Mode to obtain different effects.
For example, you can invert the Opacity layer, to have a Black output, and use the Multiply Bland Mode, to have a Black fog effect: Happy GPU rendering,
ciao,
Beppe

Dear Beppe,

Thank you so much for your excellent step by step description. Bless you. It looks like it will be just what I need, both for how to make the depth pass and to understand the compositing process!

However, I haven't finished going through it yet. I stopped at Number 4. It seems like either I have a different version of Octane that you do, or something else is going wrong.

If you take a look at the file I am attaching, you will see the pop up menu looks different. In yours, there is something called Beauty, in mine, there is Main and Beauty is a Popup with many different passes in it, none of which just says "Beauty".

Please let me know what you think is going on so I can continue your excellent tutorial.

Thanks again,

Joe.

Hi Joe,
yes, the Main pass is equal to the Beauty pass, but please upgrade c4doctane to the latest stable version 2021.1-R2:
viewtopic.php?f=85&t=78663

ciao,
Beppe

Dear Beppe,

THANK YOU!!! It works like a charm.

I still have to understand the compositing process better in Octane and would like to read more about that (if you happen to know any online resources that would be great).

However, this works perfectly and I don't have to step out to an external compositing program to composite it. That is great! Although I would still like to know how to export or render out a separate Z-depth pass...

In the meantime, this might be everything I need!

Cheers,

Joe.

Hi Joe,
great

About "how to export or render out a separate Z-depth pass...", at step 1 you should have already activated it in the Render Settings/OctaneRender/Render AOV Group panel, that corresponds to the old Multi-Pass panel.

Happy GPU rendering,

ciao,
Beppe

Hi Beppe,

I am doing a small test render of my file and I noticed that the composite is not rendered. When I opened some of the rendered frames, they seem to just be the beauty pass (without the composited Opacity layer masked with the Z-depth pass).

What am I doing wrong? When I go to the picture viewer and switch to Single-Pass, one of the passes is called Out1 and it looks correct. However the frames that are saved seem only to be the beauty pass before the Z-depth.

Edit: I just noticed that I do not have a filename entered in the Render AOV Group area in the render settings. Does that have something to do with it?

Thank you.