I use Photoshop almost exclusively for focus stacking. Been running CS6 forever as it doesn't make sense to pay an outrageous subscription for a program I use a couple times a month to do focus stack. With the arrival of Catalina (and the death of CS6), I thought I'd try purchasing a focus stack application so I could stop using Photoshop for that purpose.
For the most part, Focus Stacker does the job fine. It is, however, missing one crucial feature and a couple others would be nice to have:
1) As best I can tell, there is no manual crop function. This is absolutely essential to a program such as this one. It's a real shame I have to load the finished photo into some photo editing app just to crop the part I want to keep.
2) It would be really nice if there was a simple control to adjust (brightness) levels.
Other than that, it seems to work fine. A little faster than Photoshop (because there are several manual steps involved when using Photoshop). More speed would be graciously accepted, but I understand that stacking 40 20-megapixel images is going to take a while.