Hey guys, I know this topic was dead for last 5 years

, but I still think that it would be better to ask my question here.
So here is the question: I want to convert information from my specular channel into mask. But it doesnt work in any ways that I have tried. What I mean is that I want to take information from Specular channel from all of layers underneath and convert it into mask. Is it possible?
Thank you!