Might be your answer. At least it is available for the Mac and handles stacking of images (also into EXR-format), masking and distortion-correction of images. It is not per se meant for astrophotography, so you would have to know what to do.

As for automation (of the aligning) - I put each of my Stacks/Stitches into separate directories and just let a script run over all these directories, applying 'autopano' or 'align_image_stack' on all files in the directory. You have to check and correct the ready.pto-file afterwards. Should run fine on an Intel Mac (after you get rid of OS/X and install Windows).

Jul 29, 2015  Stacking for Mac Users - posted in DSLR & Digital Camera Astro Imaging & Processing: Ive been using Keiths Image Stacker for my astro pics for a while and cant help but wonder what else life has to offer. All the free stacking software out there is only available for Windows though. Whats a Mac lover to do? StarStaX is a fast multi-platform image stacking and blending software, which. StarStaX is available as a free download for Mac OS X, Windows and Linux.

Edit: Since a lot of people seem to have missed the point and think this isn't helpful, let me try to put things more directly. I am reasonably certain there is not currently any free (in either sense) software for stacking that runs directly on MacOS and is anywhere close to as good as CombineZP. Docker hub for mac. I'm relatively OS-agnostic -- I have two Macs (a 24' iMac and a now rather elderly Macbook). For me, choosing between Windows and MacOS is mostly a matter of picking what works better. For stacking, I use CombineZP on a PC.

I have not been able to find anything that runs directly on MacOS that produces nearly as good of results, or is nearly as easy to use (for this task). Emulator of mac os. Hugin works quite nicely for stitching panoramas, but stacking isn't really its forte. It can sort of work, but it's semi-painful to use for the job (all the docs and UI are oriented toward stitching panoramas) and even with quite a bit of manual labor, the results from it are still inferior to what CombineZP produces entirely automatically. Bottom line: A copy of Windows + CombineZP costs less and works better than anything you can get natively for MacOS. Sorry, but that's just how it is.

Is a free panorama stitcher that also includes Focus Stacking - it runs on Linux, Windows & Mac so no problems there. Facilities include alignment correction, so that if you are not using a tripod you can still stack without problems. To quote the manual: Although Hugin is essentially a panorama stitcher, like other GUI front-ends[*] it has a range of advanced features: Among the Hugin workflow options, it is possible to correct exposure[ ], Vignetting and White balance[] between photos; generate HDR, exposure fused[ ] or focus stacked[] output from bracketed photos; or use 16bit and HDR input data natively. Photos can be digital or scanned, and taken with any kind of camera. A full range of lenses are supported, from simple cameraphones to obscure fisheye[*] lenses. Hugin supports various output projections including a range of spherical, cartographic, and camera projections. Hugin supports panoramas taken with multiple rows of photos, with or without bracketing.

Bracketed photos can be handheld, taken using a DSLR bracketing function, or as consecutive panoramas shot at different EV exposure levels. Hugin can produce successful panoramas shot with cameras that always shoot using auto-exposure and auto-whitebalance. Hugin also supports the use of masks which means that you can exclude parts of images you don't want to appear in your panoramas, or include parts of image you specifically want to appear in your panoramas. Is an open-source command line utility that can accomplish focus stacking, although it more typically is used for exposure fusing.