Astrophotography Software for Mac: What Actually Runs, and What Doesn't

If you have just started astrophotography on a Mac you have probably already hit this: nearly every tutorial you find tells you to download DeepSkyStacker, and DeepSkyStacker does not run on macOS. Neither does AutoStakkert!. Neither does RegiStax. Neither does Sequator.

That is not an oversight on anyone’s part. Those tools were written by people scratching their own itch on Windows, some of them two decades ago, and they are free. But it does mean the standard beginner advice is written for a machine you do not own, and working out what to do instead is genuinely harder than it should be.

This is the honest list.

What runs natively on macOS

Siril — free, open source, and the best starting point for deep sky on a Mac. Calibration, registration, stacking and a full post-processing set, with a scripting language that can run an entire session unattended. Apple silicon build available. The catch is not capability, it is that Siril does what you tell it and nothing you did not: the scripts in the manual assume you already know which one matches your data.

PixInsight — around €300, cross-platform, and the highest ceiling in the field. Also months to learn. It is not a first program and its own community will tell you so.

GraXpert — free, open source, cross-platform. Gradient removal and optional denoising. Not a stacker; it fixes one specific problem in an image you already have.

Starnet++ — free star removal, runs on macOS. A step in a workflow rather than a workflow.

Astro Pixel Processor — paid, cross-platform, Java-based. Well regarded for mosaics in particular.

Akastroid — what we make. Native on macOS including Apple silicon, covers deep sky and planetary in one program, free to try. More on where it fits below.

What does not, and what people try instead

DeepSkyStacker is Windows-only and has been since 2004. There is no Mac version and there is no plan for one.

AutoStakkert! is Windows-only. It is also the standard for planetary and lunar stacking, which makes its absence the most painful one on this list.

RegiStax is Windows-only and unmaintained since 2011.

Sequator is Windows-only. For wide-field nightscapes on a Mac, Starry Landscape Stacker is the usual answer instead — it is Mac-only, paid, and does the same job.

The usual advice is “just run it under Wine” or “use CrossOver” or “install Whisky”. Be aware of what that is actually like in 2026, particularly on Apple silicon:

• Homebrew disabled the WineHQ casks in September 2026 over Gatekeeper signing.
• Apple’s Game Porting Toolkit, which several guides still reference, is not a general-purpose answer and has been through breaking changes.
• Whisky installs, but getting a working runtime under it is its own project.
• Rosetta 2 does not help. It translates Intel macOS binaries, not Windows ones.

We tried to get RegiStax running this way on an Apple silicon Mac for a comparison benchmark and gave up after an hour. It is not impossible, but “install Wine” is not a one-line answer and you should not plan your workflow around it.

A virtual machine with a real Windows licence does work — Parallels or UTM with Windows on ARM, plus x86 emulation for these particular programs. It costs money, disk and patience, and you are then maintaining a Windows install in order to process pictures.

What this means in practice

A Mac astrophotographer’s realistic options are:

Deep sky: Siril free, PixInsight if you want no ceiling, Akastroid if you would rather the software made the routine decisions and showed you what it measured.

Planets and the Moon: this is the real gap. AutoStakkert! plus RegiStax is the free standard and neither runs. Your options are a Windows VM, or a program that does lucky imaging natively — which is part of why we built planetary into Akastroid rather than leaving it to a second tool.

Nightscapes: Starry Landscape Stacker, Mac-only and paid, or Siril.

Where Akastroid fits

Akastroid is a native macOS application — Apple silicon and Intel — that handles both deep sky and planetary. Load a folder of sub-exposures or a planetary video and it works out which it is, measures your frames, and decides the calibration, stacking, gradient removal, colour and stretch for itself. Every decision it makes is shown with the numbers behind it, so it is not a black box you have to trust.

It is not more capable than PixInsight and does not claim to be. What it is, on a Mac specifically, is one program instead of a Windows VM plus three downloads.

Free to try on your own data, nothing uploaded, no account.

Download for macOS · Compared against Siril, DeepSkyStacker and PixInsight

A note on Apple silicon

M-series Macs are genuinely excellent for this work — stacking is embarrassingly parallel and the unified memory means a 300-frame session does not thrash. Akastroid ships a native arm64 build; Siril, PixInsight and GraXpert all have Apple silicon builds too. The only thing Apple silicon makes worse is the emulation route, because you are now two translation layers away from a Windows binary instead of one.

If you are buying a Mac for astrophotography, memory matters more than cores. A long session’s calibration masters are the thing that fills RAM.