a problem about shadowcatcher

Development Programming & Scripting Blueprint
1

I followed the first six minutes of this video（not use composure that he did）

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Unreal Shadowcatcher realtime performant with Alpha Channel - YouTube

But when i follow his ,using “before tonemapping” ,the shadow semms like blur ,

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then i use “after tonemapping” ,the shadow become right,but actor jitter with white edge.

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I think very close to the AR shadow catcher. How should I modify it?

2

Does this method work in Unreal Engine 5.4? and in pathtracing mode?