I am learning Chopin black keys etude. Anyone have any tips?
Well, my comment above wasn’t exactly sarcastic as I do believe the fingers are really what makes this smooth as opposed to the ubiquitous (and problematic) advice often given that you have to rotate through the entire thing. First thing I would do if I started to learn this is to block all of the groups into chords based upon the chosen fingering and get the positions down first. Then slowly separate into individual notes and focus on maximum finger action and minimum rotation.
Try to not hit any white keys with the right hand.
Use your fingers!
Hit the right notes; there's a different Etude for wrong notes.
I never really found actively rotating solved any problems for me in this Etude. You might see some small shaking of my arm but I don't think about it, it just naturally happens as a result of being relaxed enough. But other people might experience things differently.