The last thing I do in the raw-conversion part of development (i.e. in Adobe Camera Raw or in AP's Develop module) is capture sharpening. My experience has been that the precise amount of capture sharpening within modest limits isn't critical to the final result. So I just eyeball the result, starting from some slider-values (my own pre-sets in ACR) that have worked in the past.
But I'm a bit puzzled by AP's use of a percentage in the Radius slider of Detail Refinement. If this is a USM routine, I'd expect the value in "radius" to be the number of pixels surrounding detected edges where contrast will be increased (by the "amount").
What does a percentage radius measure? Percent of what?
(Or am I wrong to assume that this is a USM routine? Is it, instead, some form of de-convolution?)
Thank you.