Weird behavior in Avid w/ external inserts

I’m attempting to position text as an insert. The text was rendered in After Effects as ProRes 4444 with Alpha for obvious reasons.

I understand from other posts and my own testing that the insert module in Avid doesn’t work with insert layers that have alpha channels. So I’m importing the text inside Mocha Pro in lieu of using the automated 1st below insert layer.

That works just fine inside Mocha Pro. But anytime I change the insert layer in layer properties to the imported asset instead of ‘Insert Layer’ Avid doesn’t render the insert. Just nothing happens. If I switch back to ‘Insert Layer’ Avid renders as expected, but I lose the alpha channel.

Maybe I’m missing something, but shouldn’t a custom imported insert asset work for rendering the plugin in Avid?


Hi @jan, there is a problem with clip files rendering to the host if they are imported via the Mocha GUI.

If you want this to render, convert your ProRes clip to an image sequence, such as TIF or PNG, then import the sequence via the Mocha insert clip dropdown.
We have an outstanding bug to fix clip imports for host renders, so the workaround, for the time being, is using sequences.

Which version of Media Composer are you using so we can check the Insert Layer alpha issue?

Hi @martinb. That would make sense. I’m on the latest version of MochaPro on Win10. I’ll try the image sequence work-around and confirm that this works.

And it’s Avid 2022.7 (also latest).


Confirming that switching to TIFF sequence solves the problem.

Alpha problem from insert layer persists with sequence as well, and both linked and consolidated. Just doesn’t seem to travel across. Shows as black background inside Mocha Pro and in Avid (and Avid 2022.7).

Alpha to layers below isn’t supported in Media Composer yet, but you can render the Insert:Composite instead to combine the two via Mocha’s renderer, then select your preferred blend mode.