Does Observatory use a single library like Photos or iTunes?

No. An Observatory library is treated as a document. You can create as many different libraries as you wish, and have multiple open at the same time. You can even create temporary libraries which you do not explicitly save to disk, but discard after use.

When importing images into a new library, does Observatory copy all images?

No. Importing only copies the metadata of the images into the library. The library contains links to your images.

Can I rename image files or move them after I have imported them into a library?

Yes. As long as you do not move your files to another disk, you can rename and move them without breaking the links. And even if you do break the link, it is easy to restore it from within Observatory.

If I import the same folder twice, will this result in duplicate images?

No. During importing, Observatory computes an SHA1 hash of each image file and stores it along its metadata. This slows down importing, but ensures that you will never end up with duplicates, even if you rename or move images between imports.

Does Observatory support the images of my camera?

Observatory supports FITS, XISF (PixInsight), SBIG, DNG, NEF, CR2, TIFF, JPG, and many more image formats. It uses the system-level support for RAW images provided by macOS. The list of supported cameras can be found here:


We cannot guarantee that this list is up to date or correct though. If you are concerned whether it will support your files, then please contact us before purchasing Observatory. Please refrain from sending images by email, but share one or more with us using for example Dropbox. We will send you a screenshot if it is supported.

What are Observatory’s software and hardware requirements?

Observatory requires OS X 10.11 (El Capitan) or macOS 10.12 (Sierra). A minimum of 4 GB RAM is required, and a SSD is highly recommended.

Observatory internally uses 32 bits floating point for each pixel in each channel. A 16 megapixel grayscale image expands to 64 MB in RAM, and a 16 megapixel RGB image to 192 MB. Observatory’s RAM utilization is not yet fully optimized, and currently it may use a little more than twice that for each image. If an image uses the calibrate adjustment, the calibration frames are loaded into RAM as well, and when stacking, all its images are loaded into RAM. The practical size of a stack is therefore currently limited by the available RAM.

Does Observatory take care of all my image processing needs, including stacking video clips of planets?

No. The primary goals of Observatory are to help you organize your images, make it incredibly easy to obtain images from professional observatories and integrate the image formats used in astronomy with macOS. Observatory is able to calibrate, align and stack images, and make minor adjustments to them. It has not been fully optimized yet, but work is underway to improve this. Observatory is an evolving product, and a lot more is coming.