Hi water molly
welcome to this Apple (user-to-user) Community,
Re: Astrophotography software: I'm wondering if there are any Mac users here into Astrophotography, Deep sky and planetary imaging.
Sorry I'm no expert on the topic, or the software ... yet, at the very least, a reply will get your discussion underway, and allow others more opportunity to reply. I only found a few discussion threads that mention astrophotograhy, Maybe your post to the community will start something!
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Discussion thread: 3 years ago: "I'm just starting out in astrophotography ..."
Mac Studio base vs. Ultra for computation… - Apple Community
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Discussion thread: 18 years ago! : "I use Aperture to organize all my astrophotos" ...
Aperture vs Photoshop CS3 - Apple Community
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Re: " ... seems that whatever free software that is out there and commonly used is Windows based and/or not compatable with the latest Mac OS"
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Online:
"Getting started with Astrophotography on the Mac" was one of the many offerings available when searching
Again, I can not vouch for the authenticity and wisdom contained in the article, which looked ok to read.
https://www.macobservatory.com/blog/2018/8/1/getting-started-with-astrophotography-on-the-mac
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Re: "I'm also hesitant to download anything from unofficial or third party websites or websites that have suspicious credentials."
There were some free and paid apps available in the App Store, when I searched "Astrophotography".on my Mac.
(I had to stop looking through them when "astrology" apps started showing up though.)
Sorry I have no idea of the worth of any of them. Please be aware some developers of "free" apps may insist on a subscription if you want to continue, or to use certain features, after a trial period. If you consider downloading any app: a close look at the app description should reveal whether there are "in-app purchases" before choosing.
All the best :-)