I use Houdini 20 to output the Arnold cryptomatte AOV layer, but it cannot be picked up in Nuke. I don’t know what the problem is. Please help me. I tested that there is no problem in version 19.5. Here is my simple test file.

version: houdini 20.0.547 & arnold 6.2.5.0

I'm not sure what the current problem is exactly, but with the new workflow it's easier to customize and will require fewer nodes.

Fantastic, I tested it and it is possible to output cryptomatte through Husk. Thank you for your reply. I wasn't aware of these new nodes and new solutions updated in Arnold.

Looks like it's still broken in 20.0.547 and it's matching arnold version. This was broken for so long in previous version on Linux and it was fixable by adding LD_LIBRARY_PATH="${HDSO}" to houdini.env. But even that trick doesn't work with houdini 20 and htoa 6.2.5.1

We had this problem as well and for us the solution was to make sure the product type attribute on the render product node was set to "arnold" instead or the default "raster".

I solved by this way. You can check my hipfile!
I just adjusted the scenegraph structure, and something else.
By this way, you can retain your custom vars!

portezhang
I solved by this way. You can check my hipfile!
I just adjusted the scenegraph structure, and something else.
By this way, you can retain your custom vars!

You can check the exr file in nuke, and they are able to use.