HELP! How do I assign a post processing volume into postprocessinput1 on the scene texture node?

So I’m currently creating a transition between two post processing effect similar like this one: Outline Transition Effect Using Postprocess Material - (UE4) - YouTube

However in the tutorial he’s transitioning between postprocessinput 0 and diffusecolor (on the scene texture node), I want to transition between two post processing volumes. How do i assign a certain post processing volume that already exists on the scene into postprocessinput 1 ?

I think you misunderstand what postprocessinput 0 is, it just means the final image rendered including post processing effects. Post process volumes can’t be used as inputs in a material, they are just the containers that post process materials are assigned to.

You can however blend between two post process volumes (that can have any number of post process materials assigned to them), by controlling their “blend weight” parameters either from a blueprint or a sequence.

This will only do a simple “crossfade” between them, but I think you can also achieve that spreading effect in the video, if one volume does the split between your effect1 and normal look, and the other volume does the opposite, between normal look and effect2.