Matte problem

[amanite666]

PEASE HELP !!!

In C4D, I have rows of cells lined up behind each other in a clone. Each cell contains a nucleus.
For my future compositing, I need to isolate all the nuclei, without the cell membrane that is in front of them. But the membrane's ior must remain effective.
In my final pass for these nuclei, all those in the foreground must be visible, while those behind them should only be visible when the cell membrane is not in front of them.

Thank you in advance for your help !

[bepeg4d]

Hi,

Have you tried with Custom AOV:
https://docs.otoy.com/cinema4d/CustomAOVs.html
Capture AOV:
https://docs.otoy.com/cinema4d/CaptureAOV.html
?

ciao,
Beppe

[amanite666]

Yes, I think the solution could be with custom AOV but I don't find the way to achieve exactly what I want.

[amanite666]

Hi,

Have you tried with Custom AOV:
https://docs.otoy.com/cinema4d/CustomAOVs.html
Capture AOV:
https://docs.otoy.com/cinema4d/CaptureAOV.html
?

ciao,
Beppe

Yes, I think the solution could be with custom AOV but I don't find the way to achieve exactly what I need.

[bepeg4d]

Ok, please have a look at this example scene:

RefractionCustomAOV.c4d.zip

(339.14 KiB) Downloaded 9 times

Let's say that we need a mask for the red capsule inside the glass sphere:

You need to go to the Basic tab of the red material and enable the Custom AOV channel, then set it to Custom2, then go to Render AOV Manager tab and create a new Custom AOV sets to 2 and visible after refraction:

ciao,
Beppe

[amanite666]

Thank you so much Beppe!!

It's almost what I need. But, in my scene, I have multiple cells (cloner) and on the custom pass, there is a lot of reflexions with other cells. Il put a Ray swich node in the specular material whit all the value to 0, except for tha camera ray (1). It's better but I've got alwys some refraction. Any idea on how the achieve this? I realy need just the capsule.
Thank a lolt!

(I put my C4D file in the message)

[bepeg4d]

Ok, just for calculating the mask, you can set the Specular Depth to 2 in Kernel panel:

ciao,
Beppe

[amanite666]

Thank's again Beppe, but it doesn't work with a different camera angle.

[bepeg4d]

Weird, it work in any direction here, with a default Specular material:

The ray should't have enough depth to show extra refraction

ciao,
Beppe

[amanite666]

Thank you so much! You saved me!
Once again, it wasn't that complicated, but I had to figure out how to combine the different parameters to achieve my goal.
Have a great day!
Ciao!