DeepSkyStacker is a freeware for astrophotographers that simplifies all the pre-processing steps of deep sky pictures.
- - DeepSkyStacker is the most popular Windows alternative to Siril.
- - DeepSkyStacker is the most popular free alternative to Siril.
SAOImageDS9 is an astronomical imaging and data visualization application. DS9 supports FITS images and binary tables, multiple frame buffers, region manipulation, and many scale algorithms and colormaps.
- - SAOImageDS9 is the most popular Mac & Linux alternative to Siril.
- - SAOImageDS9 is the most popular Open Source alternative to Siril.
FITS Liberator GUI image processing software has meant that it is even easier and faster to create color images using raw observations from a range of telescopes.
FITS Liberator Features
Regim makes some processing steps that are unique to astronomical images a bit easier. These steps are calibration (dark and flat), deblooming, registration, combination, color calibration, gradient removal and some more.
PixInsight - Advanced Image Processing. PixInsight is a modular, open-architecture, portable image processing platform available for FreeBSD, Linux, Mac OS X and Windows.
- - PixInsight is the most popular commercial alternative to Siril.
Fitswork is a windows image processing program, mainly designed for astronomic purposes. It contains batch processing, histogram functions, many filters, etc. Fitswork works entirely in floating-point arithmetic.