Render2d / Scope weird effects - how to fix? [bug?]

I have simple scope based on render target. Generally view is brighter than around, normal view - no idea why?

but when my SceneCaptureComponent2D (attached front of Scope) is in shadow, rest of game visible in scope, even areas in full Sun looks much darker:

This is not normal. I miss something? Also I can’t see any difference changing SceneCaptureComponent2D post process settings.

Thank you++