Linda, here’s a link to a Helicon stack that I posted last spring, Red Maple flowers and seeds.
Your post here got me investigating further, so I went in and restacked the same 10 images. I was surprised by the results! First, I saw little if any difference between using the B method with varying parameters and the C method also with varying parameters. That should be said with the caveat that while these flowers are a “close-up”, they are not a macro shot, so I’ll need to revisit the effects of parameter choice on sharpness in a true macro shot also. What I did see, were some places where last year’s version did a better job of retaining sharpness and one situation where the new version avoided a common artifact. I just emailed these two clips “new” and “old” to Helicon with my comments, which I’ll repeat here. The blue and green arrows point to spots where there is less sharpness in the “new” stack, while the yellow arrow points to an area where the old version left a blur around the edge with the new version shows a clean background.
Old version
New version
Since the PS image shows good sharpness, it cannot be your lens & camera.