Starry Sky Stacker reduces noise in pictures of the night sky that are captured as a sequence of exposures using an equatorial mount or some other mechanism that ensures that stars move very little either during or between exposures. Starry Sky Stacker aligns the images to compensate for errors in tracking,
assigns a quality estimate to each image, allows the user to select images based on the quality estimate, and finds the median. The resulting image has much less noise than any of the original images.

What’s New

Version 1.4.1

Built for M1 Macs. I do not have an M1 Mac and cannot test this. Please send me mail if you have an M1 Mac and experience any difficulties.

Fixed a problem that could occasionally cause a crash on start up when running on macOS 11.

Minor UI changes to work better with macOS 11.

Other minor bug fixes and UI adjustments.

Ratings and Reviews

4.2 out of 5
13 Ratings

13 Ratings

Calvin Knight ,

Updated Review

I purchased this program a few years back and had unfavorable results and gave a "less than stellar" review. Recently I returned to it, spent quite a bit of time reading the updated instructions and noticed some version improvements. After spending quite a bit of time with it and some other imaging software I got results better than I had expected. My final images seemed like they still have quite a bit of noise, but after running through other software the final image was stunning.

Developer Response ,

Could you contact me directly please? Launch Starry Sky Stacker and in the menu bar select "Help->Contact Developer". Starry Sky Stacker is working well for many people. I would like to find out why it is not working for you.

Fchixon ,

Great Program and simple to use!

I like this program. It makes a quick and simple job of stacking my images. I use a Nikon 810a and I can use the raw files directly. I have determined that using in-camera long exposure dark reduction(does dark removal in camera) does a fine job so I have not needed to use dark subtraction directly in the program. I will try with some older stacks I have as well. Being able to select darks, flats, and bias frames from other directories would be nice to have since I keep a library of those that are not often in the same directory as my light frames.

I use an iOptron tracker for my Milky Way shots, so I end up using this program instead of Starry Sky Stacker. Then I composite my stuff manually.

The fact that I can use my RAW files directly from Canon, Nikon and others removes a lot of steps. It does a great job of stacking. It definitely works better with uncorrected lens from Lightroom (as the help in SSS says).

I use it for normal lenses as well as my telescope. EXIF data is missing for my telescope and it does not seem to see my 14mm Rokinon lens either, but it just a warning. Lightroom sees the lens though. It would be nice to be able to add the lens data (if it matters to the program) when I load the images. If it does not matter, then it does not matter.

Highly recommended for tracked shots.

TomS51 ,

Happy with program

Have used this on three deep sky images and have been very happy with the result. It greatly reduced the noise and improved the quality of the images, which were based on sets of 12 to 40 images. The automatic image quality rating did not work so well in the 40-image case. Some of the images that were classified as poor were not so bad and some that were classified as good were not so good. You definitely want to check the image quality manually and not just rely on the program. Its easy to manually examine the images and eliminate ones that are not good. I found that the mean worked slightly better than the median in one case.

App Privacy

The developer, Ralph Hill, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Collected

The developer does not collect any data from this app.

Privacy practices may vary, for example, based on the features you use or your age. Learn More


  • Family Sharing

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