Astrophotography Image Processing with Graxpert, Siril & GIMP
Second Edition (version 2.0)
24th June 2025: This guide is currently unavailable. It is being revised to reflect the changes in the newly released version 1.4.
Installation
The links below help you install the software you need:
Siril: https://siril.org/download/
Starnet: https://www.starnetastro.com/download/
Graxpert: Latest versions including pre-release https://github.com/Steffenhir/GraXpert/releases
GIMP: https://www.gimp.org/downloads/
The Guide
The book offers clear, step-by-step instructions to help you transform RAW and FITS images of astronomical objects into stunning final images. With a focus on clarity and accessibility, it breaks down the core processes to ensure that even beginners can follow along with ease.
In addition to traditional One-Shot Color (OSC) cameras, including both dedicated astrophotography cameras and DSLRs, the guide also covers the use of smart telescopes like the ZWO Seestar, making it an essential resource for a wide range of astrophotography enthusiasts.
Support Free Software Development
If you use this software and would like to support it’s continuing development please donate here, I do.
https://siril.org/donate/
https://www.gimp.org/donating/
GraXpert does not currently have a donation page.
Downloads
The guide uses images of M31, the Andromeda Galaxy as a worked example. Here’s how to get the files so you can follow along. Right-click the link below to download a zip file containing M31.fit
M31.Zip
M31Final.Jpeg : As the name suggests this is the version after all processing stages, as described in the guide. This file is shown below so you can see what can be achieved using these free software systems. (Right Click to Download)
