Where is the alpha channel?


as in the picture shown, why cannot I find an alpha channel in the OpenEXR Multichannel file Output section?
everything else is there (it has been rendered and saved!). In the Picture you can see a trick to create an alpha channel with a color ramp. That is not precise, is it premultiplied or what ? What am I missing or is the alpha channel hidden within the “combined” channel? (and why is it not a separate channel in the image node?).

Please Help me out!



Have you actually rendered and saved the alpha channel data, i.e. used rgba instead of plain rgb?

yes, I did.


just try to load an openEXR Multilayer file, not renderlayer, in the compositor and look for the alpha channel?!

best regards

You could connect the combined output to a ‘Separate RGBA’ node. You should then be able to access the alpha channel (A) of the combined render

Thank you Richard,

perfect, that’s it! :eyebrowlift:

best regards,

how can I mark this as “Solved” ?