Alpha channel not working

[Davide N]

Hallo,

i have a footage created on After Effect i need to play on Qlab. This footage are flames i need to start and then stop during the show. These flames overlay the background.

I exported (alpha channel + RGB) with Quicktime format codec HAP Alpha that Qlab supports.

When i play it on qlab a white background is shown under my flames.

Is there something i miss?

I use After Effect on Windows so i can't make a try with ProRes 4444 codec.

Any help?

Thanks 

[micpool]

This is usually because you have set the background in AE to something other than black and have premultiplied.

A straight RGB+Alpha millions+  in HAP Alpha should work as should  a premultiplied RGB+Alpha millions+  in HAP Alpha, but only if your AE background is set to black.

Mic

[Davide N]

Black Background made the trick.
Thank you very much