When using the clone stamp tool on the high frequency layer of a photo there is no effect to remove blemishes. It is like I'm painting with zero opacity. I't reset tools and preferences to no avail. For reference I'm following the tutorial of Aaron Nace of Phlearn. BTW: it works in 2015.1.2
I have followed Aaron's way for over a year now - the clone stamps does exactly what you described here, from time to time - and the same, I close and reopen, rest the tools, all to no avail. I never know why it starts working again, or why it stops. Just wondering if you, after four years, have figured anything out. I"m exhausted, need to get this job done. Any help is greatly appreciated.