The pixels were wrapping around and mixing back into the visible pixels again. Ususally this works without incident, but some plugins aren’t programmed to handle true 32bpc, and apparently, paint is one of them.
Normal levels should work with clipping, but I only use the individual controls so cannot guarantee correct programming 100%. You only have to clamp the paint comps and you apply the clipping after, not before. Apply it to all the paint comps so you don’t have to wait to render to find out where the errors are.
Since it’s working for you, just keep doing the same thing. I’m glad to hear my trick worked.
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