I have Helicon and am satisfied with it for general use. However, I understand that Zerine is preferred for extreme macro where hundreds of images are involved. This month's issue of Popular Photography (generally not a very high end publication) had an article on macro showing stunning images of insects by John Hallmén who uses Zerine.
Hi Bill,
I've processed stacks of 100+ images (21 MP each) with Helicon Focus, so that would seem to be not a big issue with HF either. I have not compared the memory use between HF and ZS, nor have I methodically timed the stacking operation, but they seem comparable.
I do know that the author of Zerene, Rik Littlefield, has a lot (40+ years) of experience with stacking images of microscopic and macroscopic subject matter. That's why he developed his own stacker, trying to optimize the process for 'deep' stacks with many slices, as are common at those magnifications (DOF per slice is minimal). The algorithms used for stacking are quite similar between ZS and HF.
For those on an Adobe-centric workflow, e.g. with Lightroom, HeliconFocus is able to Raw convert, stack, and
output the result as DGN file, which might be a benefit (although I personally do not use conversions to DNG). I do not know how good it works, e.g. dealing with Chromatic Aberrations. Helicon's integration with Helicon Remote (also available for Tablets) may also be a benefit.
Both programs support automatic focus rails, like the StackShot.
Cheers,
Bart