Question How to render out post fx on zero alpha background??

Using HDRP

My setup is - Cam has background set to black with zero alpha, The recorder is using image sequencing with alpha.

The problem is if there are any transparent surfaces or bloom is in use, it will ONLY work on opaque objects, meaning they wont be in the final render images if its casting on the cameras alpha background

How do it set my HDRP to use postfx and objects using transparent surfaces when there is isn't any opaque objects behind them?

Visual Explanation:

Camera with black color background and zero alpha (You can see the green bloom on the edges from the post fx bloom)



The rendered image using recorder (bloom is not present) (used a black gradient on background for you to see it better and that's obviously not working)



Unity, what am I missing here, a tick box, some render order?

 

Betty BOOP!

 

Just wondering if I'm talking ancient Egyptian or using the wrong terminology. Is there a way to render out bloom post fx over an alpha background or not? UNITY?!

 

BOOP

 

By "final frame" are you talking about adding it through premiere pro in post? Not sure what you mean.

Unfortunately I have multiple meshes animating that require bloomed edges, these meshes interweave, as well has have different emission values. so it would be a manual nightmare to add it in post outside of Unity.

Ideally there needs to be away to do this in some custom render or post processing order - Virtual Production platforms and pipelines both real time and offline assets will need this option

Is there any other kind of hacky way to achieve the result I'm after in Unity right now?

 

BHOOP!