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<translate>=Siril= <!--T:1-->
+
<languages />
Other languages: [[Siril/fr|voir la page en français.]]
+
<translate>
 +
=Siril, a free astronomical image processing software= <!--T:1-->
  
 
<!--T:2-->
 
<!--T:2-->
Siril was meant to be Iris for Linux (sirI-L). It is an astronomical image processing tool, able to pre-process images, help aligning them automatically or manually, stack them and enhance final images. The manual alignment capability makes it well fitted for amateur astronomers having a low volume of images and bad quality images that automatic tools fail to align properly. This page is the page for the new version of Siril, legacy [http://sourceforge.net/projects/siril/ Sourceforge project] and [http://dulle.free.fr/alidade/siril.php?lan=en website] are unmaintained.
+
Siril is meant to be Iris for Linux (sirI-L). It is an astronomical image processing tool, able to convert, pre-process images, help aligning them automatically or manually, stack them and enhance final images. In 2017, it also began to work on Mac OS X and Windows.
  
<!--T:3-->
+
<!--T:79-->
The software has been updated to recent operating system libraries (mainly to GTK+3) and still under development and quite unstable. Many improvements have been done over the previous unmaintained version, including better handling of conversions, image sequences and errors, improving the GUI, and lots of bug fixes. As of October 2013, the command line is being reactivated; the idea is to continue updating the commands so that they work with the new internal structures, and then add them in the GUI. [[Siril:Commands|Here]] is the list of commands currently available.
+
{{:Siril:Links}}
  
<!--T:4-->
+
<!--T:60-->
Siril's works internally with FITS images, unsigned 16-bit for each pixel information. All images you want to process with Siril thus need to be converted, except for SER sequences which are converted on-the-fly, see the '''[[Siril:Manual|stacking tutorial page]]'''.
+
<randomimage size="600" float="center" choices="Lovejoy_300mm_Cyp.jpg|Cassiopeia_Cyp.jpg|Lovejoy_VB.jpg|Lovejoy_Cyp.jpg|Lune-TFG-2014-04-07.jpg|Star-trails.jpg|M33.jpg|NGC7635.jpg|Siril_M8-M20_processed.png|Jupiter.png|Cygnus_loop_fphg.jpg|M27_Cyp.jpg|M33_Cyp.jpg">This image was processed using Siril, see other [[Siril:Results|processing results]].</randomimage>
 +
 
 +
==Who should use Siril?== <!--T:22-->
 +
Siril is targeted to '''amateur astronomers''' having acquired images and wanting to process them in a semi-automatic way. It provides a more user-friendly interface than Iris' command line as well as more modern and powerful processing algorithms, but it is not yet as automated as DeepSkyStacker or Registax. It also provides a basic command line to access various processing functions.
 +
 
 +
<!--T:24-->
 +
Siril is now fully capable to pre-process and process '''deep sky''' images. One feature still missing for '''planetary''' images processing is image deformation, but it is still capable of registering and processing them in an elegant way. The new star detection registration is perfect for deep sky images, but there are also two automatic translation-only registrations, one more suited for planetary and bright nebula images, based on [https://en.wikipedia.org/wiki/Discrete_Fourier_transform Fourier transform], and another more simple targetted at deep-sky images, based on [https://en.wikipedia.org/wiki/Point_spread_function PSF] on a single reference star. Additionally, a manual alignment capability makes it also well fitted for amateur astronomers having feature-less or bad quality images that automatic tools fail to align properly.
 +
 
 +
<!--T:25-->
 +
Professional astronomers generally use 32-bit depth images, but Siril uses only 16-bit images internally (except temporary for stacking). Loading 32-bit images is supported but it will degrade them since they will be converted to 16-bit (version 1.0 will use at least 32-bit depth channels internally). It can still be useful if the intent is to produce public-friendly pictures.
 +
 
 +
<!--T:26-->
 +
And more generally, people who want to use free software on free operating systems to process images. Siril can even be used to extract previewed frames from many videos formats. For an overview, see some image processing [[Siril:Results|results]].
 +
 
 +
==News== <!--T:3-->
 +
For latest updates, see our [https://gitlab.com/free-astro/siril/activity bug and feature tracking system].
 +
 
 +
<!--T:64-->
 +
'''We are looking for volunteer translators''', for the software and for the documentation. No programming experience is required. See the [[Siril:translate|translation instructions]] page for software translation. In any case, check the status of your language translation with cyril (at free-astro.org) if you want to help.
 +
 
 +
<!--T:45-->
 +
The software is now considered stable. If you find a bug and want to report it (please, do!), feel free to report it on the [https://gitlab.com/free-astro/siril/issues bug report page].
 +
 
 +
<!--T:81-->
 +
*'''May 27, 2019'''
 +
** The new [[Siril:0.9.11|0.9.11]] version has been released. This version contains a new photometric color calibration tool, a lot of bug fixes and optimization.
 +
 
 +
<!--T:76-->
 +
*'''January 16, 2019'''
 +
** The new [[Siril:0.9.10|0.9.10]] version has been released, with bug fixes, and new astrometry tool feature.
 +
 
 +
<!--T:80-->
 +
*'''November 26, 2018'''
 +
** Insight has landed! But the Siril news here is that we migrated our source code and bug management system to gitlab! Please use this modern way of communicating with us about code and problems now. The address of the project is https://gitlab.com/free-astro/siril/ . It's been a long year for us with many unfinished business for the 1.0 version. In the meantime, we are preparing a [[Siril:0.9.10|0.9.10]] stability release for very soon.
 +
 
 +
<!--T:78-->
 +
*'''June 7, 2018'''
 +
** The new [[Siril:0.9.9|0.9.9]] version has been released, with bug fixes, and new script feature.
 +
 
 +
<!--T:74-->
 +
*February 19, 2018
 +
** A patch of the [[Siril:0.9.8|0.9.8]] version has been released: 0.9.8.3.
 +
 
 +
<!--T:75-->
 +
*January 31, 2018
 +
** The new [[Siril:0.9.8|0.9.8]] version has been released, with bug fixes, improvements on lucky imaging and Windows integration.
 +
 
 +
<!--T:71-->
 +
*December 4, 2017
 +
** A new 0.9.8 version is [https://gitlab.com/free-astro/siril/milestones/11 progressing well] and will particularly help people working on deep-sky lucky imaging.
 +
** We have also started working on features for the next major version of Siril, '''version 1.0'''. The first development, started at the beginning of the year, aims to greatly speed up the display of images and the rendering effects and this looks very promising. Other major developments will be the use of a better precision, floating point, internal image format that will give better results with some algorithms, the parallelisation of preprocessing and the creation of a high quality registration and stacking method for planetary images. It will still take a lot of time, but that will be a fully featured and fast version of Siril. Current 0.9.x versions are stable and already provide great results for deep-sky image processing.
 +
 
 +
<!--T:70-->
 +
*September 21, 2017
 +
**New release [[Siril:0.9.7|0.9.7]]. Click [[Siril:releases|here]] for past releases. Siril is now available on '''Windows''' as a beta version!
 +
 
 +
<!--T:69-->
 +
*June 20, 2017
 +
**New release [[Siril:0.9.6|0.9.6]]. Click [[Siril:releases|here]] for past releases.
 +
 
 +
<!--T:68-->
 +
*November 28, 2016
 +
**New release [[Siril:0.9.5|0.9.5]]. Click [[Siril:releases|here]] for past releases. Development of major improvements such as native 32 bit images and GEGL rendering has started.
 +
 
 +
<!--T:66-->
 +
*October 8, 2016
 +
**A new team member has given a huge effort to bring you a fantastic new multi-language documentation, both [https://free-astro.org/siril_doc-en/ browsable] and in [https://free-astro.org/download/siril-doc-0.9.9-en.pdf PDF].
 +
 
 +
<!--T:65-->
 +
*August 17, 2016
 +
**New release [[Siril:0.9.4|0.9.4]]. Click [[Siril:releases|here]] for past releases.
 +
 
 +
<!--T:57-->
 +
*October 28, 2015
 +
**First stable version available: [[Siril:0.9.0|0.9.0]]. Stability updates and minor improvements will occur in the dedicated 0.9 branch.
 +
 
 +
<!--T:58-->
 +
*June 10, 2015
 +
**New registration method available! It is now possible to register images with an automatic global star detection tool. The algorithm takes into account the translation and the rotation.
 +
 
 +
<!--T:56-->
 +
*April 13, 2015
 +
**We have been working hard on accelerating stacking algorithms on multi-core CPUs, giving SER a better support and we are also working on the two main lacks of Siril: taking into account rotation and multi-point in registration, for better deep-sky and planetary registrations. These works are in progress, and will take some weeks to complete.
 +
 
 +
<!--T:47-->
 +
Many [[Siril:0.9.7|improvements]] have been done over the previous unmaintained version. The command line has been reactivated in large proportions, see the list of currently available commands on the dedicated [[Siril:Commands|Commands]] page. New commands and features have been and are being developed. For a complete list of features, see the [[Siril:0.9.7|0.9.7]] page, [https://gitlab.com/free-astro/siril/milestones/10 the roadmap], or the [[Siril#List_of_Siril_features|list of features]] below.
 +
 
 +
<!--T:12-->
 +
Ideas for the future of Siril are stored in the issues tracking system and can be seen by version in the [https://gitlab.com/free-astro/siril/milestones milestones page]. The list of known bugs is mixed with it and the full list is available [https://gitlab.com/free-astro/siril/issues here]. The complete changelog is available either in the [https://gitlab.com/free-astro/siril/issues?scope=all&utf8=%E2%9C%93&state=closed list of closed bugs] or in the [https://gitlab.com/free-astro/siril/commits/master code source commits]. A summary is available in the news section [[#News|above]] and in the page of each release, as well as in the [https://gitlab.com/free-astro/siril/blob/master/ChangeLog ChangeLog] file. '''If you want to contribute, you are welcome!'''
 +
 
 +
==Start using Siril / Documentation== <!--T:4-->
 +
Siril's works internally with [https://en.wikipedia.org/wiki/FITS FITS] images, unsigned 16-bit per pixel and per channel. Some [[Siril:supported_FITS|other FITS formats]] are supported. All other image formats you want to process with Siril have to be converted using the Conversion tab, but some sequence files are converted on-the-fly: [[SER]] and film sequences supported by ffmpeg (which means nearly all films).
 +
 
 +
<!--T:27-->
 +
For pre-processing, Siril applies ''master'' offset/bias, dark and flat images to the current sequence. These master images thus have to be processed before processing the actual image sequence. Siril currently does not support processing multiple sequences at the same time, so each layer of the final image must be processed independently before assembling them into an RGB image.
 +
 
 +
<!--T:72-->
 +
A free [https://siril.linux-astro.fr/ online course for siril] has been set-up and new content is added regularly. Most uses of Siril will be described here with short films and exercices that allow you to learn by yourself and make sure you understood on concrete examples.
 +
 
 +
<!--T:28-->
 +
'''A [//{{SERVERNAME}}/siril_doc-en/ Web-based documentation]''' or '''[//{{SERVERNAME}}/download/siril-doc-0.9.9-en.pdf PDF format]''' for offline viewing, contain illustrated instructions on how to use particular features of Siril, along with a few videos to illustrate or describe these capabilities.
  
 
<!--T:5-->
 
<!--T:5-->
[[File:Siril_stacking_result.png|700px]]
+
[[File:Siril_stacking_result.png|600px]]
  
==Features== <!--T:6-->
+
==List of Siril features== <!--T:6-->
 
 
<!--T:7-->
 
New features are being introduced quite regularly. Usual software features are explained with screen captures on the '''[[Siril:Manual|stacking tutorial page]]''', and main features are:
 
  
 
<!--T:8-->
 
<!--T:8-->
 +
New features are being introduced quite regularly. Here is a list of main features:
 
* Native image format support
 
* Native image format support
** unsigned 16-bit FITS files
+
** Unsigned 16-bit FITS files ([[Siril:supported_FITS|other FITS]] are converted to this format on-the-fly)
** SER files
+
** [[SER]] files
** AVI files soon
+
** AVI and many other film files, their support is being dropped in favour of SER.
 
* Image conversion (to the native FITS format only)
 
* Image conversion (to the native FITS format only)
** Supported input types: 8-bit BMP, short movie files (like .AVI), NetPBM binary images, RAW DSLR images.
+
** Supported input types: 8-bit and 16-bit BMP, TIFF, JPEG, PNG files, NetPBM binary images, RAW DSLR images.
 +
* Pre-processing of images with multi-channel offset, dark and flat images
 
* Image registration; supported methods:
 
* Image registration; supported methods:
** Translation for one selected star alignment using FFT. <strike>This is not working fine at all.</strike> It appears that it works fine with good quality images (with nearly-round stars, not as bad as in the image above).
+
** Global star alignment (rotation + translation)
** Manual translation with two preview renderings of the current image with reference frame in transparency.
+
** Translation using DFT centred on an object, generally used for planetary images
** Image rotation is not implemented yet, but is under consideration.
+
** Translation using PSF of a star, generally used for deep-sky images
** Using [http://www.astro.uni-bonn.de/~theli/ Theli] is considered too, to align frames with a map (fixes image distortion, rotation, translation, according to many stars referenced by astrometry data).
+
** Manual translation with two preview renderings of the current image with reference frame in transparency
* Image stacking
+
* Registered sequence export
** Summing and median stacking.
+
** Supported export file formats: Siril FITS sequence, SER sequence, uncompressed AVI files, GIF up to 0.9.4, MP4 and WEBM web publishing video formats since 0.9.5
* Pre-processing of images with multi-channel offset, dark and flat images.
+
** Optional cropping and resizing of the exported images
* Enhancement of final images: lightness/contrast cursors on each layer, logarithmic and hyperbolic arcsin scale, negative rendering and others.
+
* Image stacking, with optional additive or multiplicative normalization
* The command line is being updated, see the list of available commands [[Siril:Commands|here]].
+
** Summing
 +
** Median
 +
** Average with rejection (percentile, sigma, median, Winsorized and linear fit clipping)
 +
** Pixel minimum or maximum across images
 +
* Enhancement and processing of final images
 +
** Lightness/contrast cursors on each layer, different scaling modes (linear, log, square root, squared, asinh, histogram equalisation), negative and false colour rendering and clipping
 +
** Background removal tool
 +
** Cosmetic correction tool
 +
* A command line for various processing functions, only available from the GUI, see the list of [[Siril:Commands|available commands]].
 +
* A star finding algorithm with PSF information
 +
* Image compositing tool, combining and aligning multiple layers (2 to 6) with custom colours into a resulting image, with luminance layer support
 +
* Plotting various pieces of information about an image sequence (FWHM, star roundness, periodic error of the mount, amplitude, background level...)
  
==Status of the new version (TODO and BUGS)== <!--T:9-->
+
==Compilation and installation== <!--T:15-->
  
<!--T:12-->
+
<!--T:16-->
The more accurate information is available in the SVN log and in a file available on the SVN, [https://free-astro.vinvin.tf/svn/siril/src/TODO TODO]. It has a precise list of things to do and known bugs. Priority for next releases are re-enabling the automatic translation registration, adding support for wavelets and LRGB.
+
See [[Siril:install|Siril installation page]]. It documents which binary packages you can get and how to build from source if needed, for multiple operating systems. Siril is a free software, licence is GPL3.
 
 
<!--T:10-->
 
'''Dec 2, 2012: Version 61 begins the support for SER files (a frame sequence container) native use.'''
 
  
<!--T:11-->
+
<!--T:73-->
'''Oct 8, 2012: Version 54 is the first version actually able to stack (manually-)aligned images.'''
+
To install standalone binaries, please go to [[Siril:releases|this page]], choose the last version and download the binary corresponding to your OS.
  
<!--T:13-->
+
==Who is behind Siril?== <!--T:37-->
* Only color images and movies have been tested for now. Movies with numerous frames will require several GB of storage for now, since each frame is written to disk with a 16-bit pixel depth
 
* Only 3-channel colour images assigned to R, G and B are possible. Other assignations are to come, for LRGB or narrowband composition
 
* FWHM function does not work properly (badly implemented, soon fixed using [[Image_Processing:Main#AstroFocuser|astrofocuser]]'s code)
 
* Automatic translation registration is not working well, but manual alignment can be done in a convenient way
 
* Warning: RAW images appear darker than in rawstudio or other RAW images visualisation tool because no automatic color and gamma correction are used
 
* Siril has light and contrast levels control with the common hi and lo cursors, but no gamma correction
 
* Median stack is limited to 50 frames to limit out of memory likeliness
 
* 16-bit BMP import fails
 
  
<!--T:14-->
+
<!--T:38-->
[[File:Siril_registration_previews.png]]
+
[[User:Vincent|Vincent]] is a computer scientist (PhD) and uses Siril as an amateur to process images from a Canon EOS, a QSI and a Basler camera on a 410mm telescope.
  
==Compilation and installation== <!--T:15-->
+
<!--T:39-->
 +
[[User:Lock42|Cyril]] is a physicist (PhD), now IT engineer at CNRS, motivating new developments and providing high quality processing algorithms to Siril.
  
<!--T:16-->
+
<!--T:67-->
Siril is currently only released as source from its subversion base. There is a package for the Arch Linux system, built from the source, [https://aur.archlinux.org/packages.php?ID=63593 '''in AUR''']. For other OS, you need Subversion (svn command) to retrieve it and autotools and gcc to compile it. Mandatory dependencies are gtk+-3.4, cfitsio and fftw. Optional are dcraw and mplayer for RAW and AVI conversion, and can be installed after Siril's install. To get the source, use the command:
+
Laurent is a senior IT project manager and also uses Siril to process images from a Canon EOS and a ZWO camera on a 254mm telescope. He manages the formatting of the documentation, using Scenari technology and the Moodle online training.
  
<!--T:17-->
+
<!--T:41-->
<tt>svn co https://free-astro.vinvin.tf/svn/siril/</tt>
+
François Meyer wrote the initial (up to v0.8) versions. Here are the legacy [http://sourceforge.net/projects/siril/ Sourceforge project] and [http://dulle.free.fr/alidade/siril.php?lan=en website].
  
<!--T:18-->
+
<!--T:40-->
(sorry for the bad certificate - this URL does not work for online source viewing with old web browsers). The source is read-only if you have no particular authorization. If you want to participate to Siril and be able to commit on the svn, send a message to user [[User:Vincent|Vincent]] here.
+
See the [https://gitlab.com/free-astro/siril/blob/master/AUTHORS AUTHORS] file for the complete list of contributors.
  
<!--T:19-->
+
<!--T:59-->
Once you have got Siril's source code, it's easy to install it. Siril is managed with autotools, so it's simply built using ./configure and make. However, the configure file is not given to allow for better interoperability and has to be generated using this command:
+
If you like the software, please help us by contributing with the Donate button on the top right. Siril takes us a lot of time and we still have to pay for the servers.
<pre>$ aclocal && autoconf && autoheader && automake --add-missing</pre>
 
Then run ./configure and make. To install Siril, use the usual:
 
<pre>$ make install</pre>
 
Default installation directory is probably /usr/local. To launch Siril, the command name is <code>siril</code>.
 
 
</translate>
 
</translate>

Latest revision as of 11:01, 27 May 2019

Other languages:
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Siril, a free astronomical image processing software

Siril is meant to be Iris for Linux (sirI-L). It is an astronomical image processing tool, able to convert, pre-process images, help aligning them automatically or manually, stack them and enhance final images. In 2017, it also began to work on Mac OS X and Windows.

<translate>

</translate>


This image was processed using Siril, see other processing results.


Who should use Siril?

Siril is targeted to amateur astronomers having acquired images and wanting to process them in a semi-automatic way. It provides a more user-friendly interface than Iris' command line as well as more modern and powerful processing algorithms, but it is not yet as automated as DeepSkyStacker or Registax. It also provides a basic command line to access various processing functions.

Siril is now fully capable to pre-process and process deep sky images. One feature still missing for planetary images processing is image deformation, but it is still capable of registering and processing them in an elegant way. The new star detection registration is perfect for deep sky images, but there are also two automatic translation-only registrations, one more suited for planetary and bright nebula images, based on Fourier transform, and another more simple targetted at deep-sky images, based on PSF on a single reference star. Additionally, a manual alignment capability makes it also well fitted for amateur astronomers having feature-less or bad quality images that automatic tools fail to align properly.

Professional astronomers generally use 32-bit depth images, but Siril uses only 16-bit images internally (except temporary for stacking). Loading 32-bit images is supported but it will degrade them since they will be converted to 16-bit (version 1.0 will use at least 32-bit depth channels internally). It can still be useful if the intent is to produce public-friendly pictures.

And more generally, people who want to use free software on free operating systems to process images. Siril can even be used to extract previewed frames from many videos formats. For an overview, see some image processing results.

News

For latest updates, see our bug and feature tracking system.

We are looking for volunteer translators, for the software and for the documentation. No programming experience is required. See the translation instructions page for software translation. In any case, check the status of your language translation with cyril (at free-astro.org) if you want to help.

The software is now considered stable. If you find a bug and want to report it (please, do!), feel free to report it on the bug report page.

  • May 27, 2019
    • The new 0.9.11 version has been released. This version contains a new photometric color calibration tool, a lot of bug fixes and optimization.
  • January 16, 2019
    • The new 0.9.10 version has been released, with bug fixes, and new astrometry tool feature.
  • November 26, 2018
    • Insight has landed! But the Siril news here is that we migrated our source code and bug management system to gitlab! Please use this modern way of communicating with us about code and problems now. The address of the project is https://gitlab.com/free-astro/siril/ . It's been a long year for us with many unfinished business for the 1.0 version. In the meantime, we are preparing a 0.9.10 stability release for very soon.
  • June 7, 2018
    • The new 0.9.9 version has been released, with bug fixes, and new script feature.
  • February 19, 2018
    • A patch of the 0.9.8 version has been released: 0.9.8.3.
  • January 31, 2018
    • The new 0.9.8 version has been released, with bug fixes, improvements on lucky imaging and Windows integration.
  • December 4, 2017
    • A new 0.9.8 version is progressing well and will particularly help people working on deep-sky lucky imaging.
    • We have also started working on features for the next major version of Siril, version 1.0. The first development, started at the beginning of the year, aims to greatly speed up the display of images and the rendering effects and this looks very promising. Other major developments will be the use of a better precision, floating point, internal image format that will give better results with some algorithms, the parallelisation of preprocessing and the creation of a high quality registration and stacking method for planetary images. It will still take a lot of time, but that will be a fully featured and fast version of Siril. Current 0.9.x versions are stable and already provide great results for deep-sky image processing.
  • September 21, 2017
    • New release 0.9.7. Click here for past releases. Siril is now available on Windows as a beta version!
  • June 20, 2017
    • New release 0.9.6. Click here for past releases.
  • November 28, 2016
    • New release 0.9.5. Click here for past releases. Development of major improvements such as native 32 bit images and GEGL rendering has started.
  • October 8, 2016
    • A new team member has given a huge effort to bring you a fantastic new multi-language documentation, both browsable and in PDF.
  • August 17, 2016
    • New release 0.9.4. Click here for past releases.
  • October 28, 2015
    • First stable version available: 0.9.0. Stability updates and minor improvements will occur in the dedicated 0.9 branch.
  • June 10, 2015
    • New registration method available! It is now possible to register images with an automatic global star detection tool. The algorithm takes into account the translation and the rotation.
  • April 13, 2015
    • We have been working hard on accelerating stacking algorithms on multi-core CPUs, giving SER a better support and we are also working on the two main lacks of Siril: taking into account rotation and multi-point in registration, for better deep-sky and planetary registrations. These works are in progress, and will take some weeks to complete.

Many improvements have been done over the previous unmaintained version. The command line has been reactivated in large proportions, see the list of currently available commands on the dedicated Commands page. New commands and features have been and are being developed. For a complete list of features, see the 0.9.7 page, the roadmap, or the list of features below.

Ideas for the future of Siril are stored in the issues tracking system and can be seen by version in the milestones page. The list of known bugs is mixed with it and the full list is available here. The complete changelog is available either in the list of closed bugs or in the code source commits. A summary is available in the news section above and in the page of each release, as well as in the ChangeLog file. If you want to contribute, you are welcome!

Start using Siril / Documentation

Siril's works internally with FITS images, unsigned 16-bit per pixel and per channel. Some other FITS formats are supported. All other image formats you want to process with Siril have to be converted using the Conversion tab, but some sequence files are converted on-the-fly: SER and film sequences supported by ffmpeg (which means nearly all films).

For pre-processing, Siril applies master offset/bias, dark and flat images to the current sequence. These master images thus have to be processed before processing the actual image sequence. Siril currently does not support processing multiple sequences at the same time, so each layer of the final image must be processed independently before assembling them into an RGB image.

A free online course for siril has been set-up and new content is added regularly. Most uses of Siril will be described here with short films and exercices that allow you to learn by yourself and make sure you understood on concrete examples.

A Web-based documentation or PDF format for offline viewing, contain illustrated instructions on how to use particular features of Siril, along with a few videos to illustrate or describe these capabilities.

Siril stacking result.png

List of Siril features

New features are being introduced quite regularly. Here is a list of main features:

  • Native image format support
    • Unsigned 16-bit FITS files (other FITS are converted to this format on-the-fly)
    • SER files
    • AVI and many other film files, their support is being dropped in favour of SER.
  • Image conversion (to the native FITS format only)
    • Supported input types: 8-bit and 16-bit BMP, TIFF, JPEG, PNG files, NetPBM binary images, RAW DSLR images.
  • Pre-processing of images with multi-channel offset, dark and flat images
  • Image registration; supported methods:
    • Global star alignment (rotation + translation)
    • Translation using DFT centred on an object, generally used for planetary images
    • Translation using PSF of a star, generally used for deep-sky images
    • Manual translation with two preview renderings of the current image with reference frame in transparency
  • Registered sequence export
    • Supported export file formats: Siril FITS sequence, SER sequence, uncompressed AVI files, GIF up to 0.9.4, MP4 and WEBM web publishing video formats since 0.9.5
    • Optional cropping and resizing of the exported images
  • Image stacking, with optional additive or multiplicative normalization
    • Summing
    • Median
    • Average with rejection (percentile, sigma, median, Winsorized and linear fit clipping)
    • Pixel minimum or maximum across images
  • Enhancement and processing of final images
    • Lightness/contrast cursors on each layer, different scaling modes (linear, log, square root, squared, asinh, histogram equalisation), negative and false colour rendering and clipping
    • Background removal tool
    • Cosmetic correction tool
  • A command line for various processing functions, only available from the GUI, see the list of available commands.
  • A star finding algorithm with PSF information
  • Image compositing tool, combining and aligning multiple layers (2 to 6) with custom colours into a resulting image, with luminance layer support
  • Plotting various pieces of information about an image sequence (FWHM, star roundness, periodic error of the mount, amplitude, background level...)

Compilation and installation

See Siril installation page. It documents which binary packages you can get and how to build from source if needed, for multiple operating systems. Siril is a free software, licence is GPL3.

To install standalone binaries, please go to this page, choose the last version and download the binary corresponding to your OS.

Who is behind Siril?

Vincent is a computer scientist (PhD) and uses Siril as an amateur to process images from a Canon EOS, a QSI and a Basler camera on a 410mm telescope.

Cyril is a physicist (PhD), now IT engineer at CNRS, motivating new developments and providing high quality processing algorithms to Siril.

Laurent is a senior IT project manager and also uses Siril to process images from a Canon EOS and a ZWO camera on a 254mm telescope. He manages the formatting of the documentation, using Scenari technology and the Moodle online training.

François Meyer wrote the initial (up to v0.8) versions. Here are the legacy Sourceforge project and website.

See the AUTHORS file for the complete list of contributors.

If you like the software, please help us by contributing with the Donate button on the top right. Siril takes us a lot of time and we still have to pay for the servers.