hard edge on glow

[jampff]

I screen recorded my issue here: probably the clearest way to see the problem: https://vimeo.com/928095854/7cf75b44e7?share=copy 

With words: I am simply dropping the stock Dissolve - vapor effect on some PNG's. I've done it many times in other projects with no issues. This time, the glow it creates is HUGE and I can't rid of a weird hard edge on that occurs on the edge of the PNG. I have already tried enlarging both the PNG and the comp quite a lot. There is room in the comp for the glow to keep extending past the edge of the PNG, not sure why it won't.

Thanks in advance.

[Mylenium]

Simply looks like you underestimate how even 0.01 % opacities can add up and produce visible artifacts and the way that particular preset creates the faux glow doesn't help due to CC Composite's limitations. Or in other words: You are using the effect in a way it probably was never meant to be used. Most of those presets are just quick&dirty text treatments. It would probably be the best to build the glows in a "clean" manner underneath the actual footage and then you can play around with blending modes , tint the contours and blur them or whatever.

Mylenium