Combine separate EXR Depth map with Beauty pass for Terragen cloudscape?

[ehangeto4]

So I spent a good 48 hours rendering a cloudscape in Terragen, which I now want to composite in AE. I rendered out all the different passes as separate EXRs rather than multi-channel, which I'm starting to suspect was a mistake. Does anyone know if it's possible to use an EXR of a depth map to add a depth matte to my beauty pass? Apologies if this is very simple, I'm a novice compositor.

I've had success doing depth compositing with multichannel images, but can't figure out how to share depth information between separate EXRs.

[Kevin Kipper]

Currently Terragen 4 Professional only saves EXR files as separate images, not multi-channel EXR files, so you didn't make a mistake in that regards.

Unfortunately, it's been awhile since I used AfterEffects and I don't have it available to provide you with an example, but in Blackmagic's Fusion I would use a Boolean operator to combine the depth pass, or any other render element, with the beauty pass.  This allows plugins and effects that expect the depth pass to be part of the EXR file to find the data.  It maybe possible in AfterEffects to do something similar, or perhaps in one layer to use the depth pass as a mask for the beauty pass in a layer below.

Here's some documentation on using Terragen's render elements:
https://planetside.co.uk/wiki/index.php?title=Compositing_Terragen_Render_Elements

[WAS]

It's far better to import separate passes as their own EXRs in AE anyway, cause when you use extractors, it extracts every frame, which actually hits render time hard. So a sequence of channels and z-depth, alpha, etc, will be much faster than extracting from layered files.