Collect and curate your astronomical images. Search 10+ professional image archives simultaneously. Create master bias, dark and flat frames. Calibrate, register, stack and adjust your FITS, XISF (PixInsight), SBIG and RAW images, all nondestructively.


• Quick Look & Spotlight: display thumbnails, previews and metadata of FITS, XISF and SBIG images in Finder and other applications. Observatory also helps your Mac index the metadata, so you can quickly find your images by dimensions, exposure time, focal length, detector temperature, right ascension, declination and more.

• Discover what’s in your images by overlaying millions of stars, galaxies, planetary nebulae, confirmed exoplanets and other objects of the Messier, NGC/IC, Tycho-2, CGPN 2000, GCVS 5.1, WDS and PGC 2003 catalogs, or use the UCAC4 and USNO-A2.0 catalogs for an additional 500 million stars.

• A flexible hierarchy: create as many libraries as you wish and keep your images organized with albums, smart albums and folders. Let Observatory keep track of your images, without copying, moving or altering them.

• Observatory automatically normalizes the image metadata in its libraries, categorizes images, and supports metadata bulk editing. You can also manually tag, rate, color code, reject or archive images. And you can add notes or attach important reference material to your images and albums.

• A nondestructive preprocessing workflow without the hassle of intermediate files.

⁃ Calibration
⁃ Cosmetic Correction
⁃ Binning
⁃ Debayering
⁃ Background Neutralization
⁃ Color Balance
⁃ Flatten Background
⁃ Chromatic Align
⁃ Register
⁃ Normalize
⁃ Stack
⁃ Resize
⁃ Rotate
⁃ Crop

• Virtual Observatory: search 10+ professional archives simultaneously and download research images from

⁃ European Southern Observatory
⁃ W. M. Keck Observatory
⁃ Gemini Observatory
⁃ Hubble Space Telescope
⁃ Spitzer Space Telescope
⁃ WISE Space Telescope
⁃ Palomar Transient Factory
⁃ SkyMapper Southern Sky Survey
⁃ Two Micron All Sky Survey
⁃ Sloan Digital Sky Survey
⁃ Digitized Sky Survey

• Plate Solving: if some of your images lack the information to relate image pixels to actual sky coordinates, Observatory’s plate solver will help you find the best match.

• Measure: image statistics, aperture photometry, PSF fitting and astrometry.

• Open FITS, XISF and SBIG images at full bit depth in Acorn, with help of our Acorn plugin.

For more information, please watch the videos and read the documentation on our website!


If you have any feedback or questions, we’d love to hear from you! You can reach us by email at

If Observatory empowers you, we would appreciate an App Store review. Your review will help other people find Observatory.

Thank you!

What’s New

Version 1.5.1

• Twenty-one new smart album criteria.
• Rotator angle support.
• Help articles about organizing images with Observatory and smart albums.

Ratings and Reviews

idonotwanttohaveanickname ,

Excellent Software

This is excellent software. Photo editing and organization with plate solving. The one thinng that would make it better is if you could plate solve without having to download 10GB of database files

Raddock ,

Great for cataloging your astrophotography images

What do you do with the organized or unorganized chaos of your astrophotography library of images as you continue to add to it over time? I end up with dozens and dozens of folders within folders sorted by date and object. Well, Observatory has shown that there’s a better way.

After importing your images (which is just a reference to your files on your drive, so very litle addition space is required) you can plate solve them for automatic tagging by all the known astronomical databases. The benefit of this is that any object you’ve purposely captured, or objects you inadvertently captured are tagged in your images. You can then create smart folders, which then subdivide your set of images into nice little categories like galaxies, nebulas, planetary nebulas, etc. Additionally you can batch tag your images with equipemnt you used, and also have those same images flow into smart folders for sets of equipment you used. The benefit being that you might have imaged a smaller galaxy or object with a wide FOV set of equipemnt, and you want to revisit that object with a narrow FOV set of equipment. This could really help in planning your imaging sessions going forward. And if you’re a completionist like I am, and intend to image the whole Messier catalog, this is a great way to keep track of that.

There are some light weight stacking, and calibration features that work well for one shot color cameras, which take folders of hundreds of images and display them in a single stack to mitigate the clutter. I would like to see some way to integrate mono channels into single stacks by selecting each channel and assigning it a color.

Additionally, a small, but powerful feature of adding astronomical image types to quicklook is amazingly beneficial. No more loading images to see what they are, when you can select one in the finder and press the space bar to see it instantly.

Some things I’d like to see come to a future version are better management of equipment, since this is only done through tagging right now. But I would like some place to store equipment I own, so it’s easier to select when tagging images. I’d also like to see FOV overlays of my equipment on some of research portions of the data. It would be great to pull up a hubble image and see how my gear could frame it, and what might be the best possible set of gear to use when planning a session on a particular object. Other information like object rise and set time based on my location would be beneficial for planning sessions.

In all though, this is a great v1 of a cataloging application for astronomical images. I look forward to what v2 can bring.

Steve-S-K ,

It Was Worth the Wait

I purchased Observatory last October hoping to be able to use it on my 6-year-old MacBook Pro to process deep sky astrophotos from my Canon EOS 60 Da. After much fiddling around, it was clear that the program was buggy and would not properly align and stack properly, if at all. I contacted the developer by email and he responded quickly asking for details. That began a chain of communications during which the application would be updated, bugs fixed and I would try it again and send my comments and often result to the developer. With the latest update, 1.0.8, the program now aligns and stacks properly. There is very little post processing available in this application and it is not intended for that. Post processing must be done in a separate program such as Photoshop. The online instruction manual is also not complete as of yet but it is progressing. There are many other features of this application that I have not yet tried. My main reason for purchasing it was to have a Mac program that would align and stack astrophotos and Observatory now does this well.

My rating of 5 stars may seem excessive but I am considering the quality of the technical support, relative price and paucity of other similar applications for the Mac. I also expect that Observatory will continue to improve.


Code Obsession LLC
79.8 MB

OS X 10.11 or later, 64-bit processor



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  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.