For Linux users, it's highly recommended to use the official KStars Flatpak hosted at Flathub. You can install the stable flatpak or try out new features by downloading the KStars Nightly Flatpak for x86_64 and arm64 architectures.
This is mostly a bugfix release with nice improvements in debayering algorithms thanks to John Evan's work on this using OpenCV. Here are some highlights:
Scheduler & Observatory Automation
Enhanced weather-based scheduling with proper abort/resume during soft shutdown
Improved preemptive shutdown with wakeup timers and better state management
Safety monitor now continues monitoring even after complete shutdown
Fixed jobs incorrectly marked as aborted when completed
Live Stacking Improvements
Added debayering support for multiple cameras including Touptek
Implemented hot/cold pixel removal
Added XISF file format support with debayering
General bayer processing refactoring
Meridian Flip & Alignment
Fixed capture operation timeouts during meridian flips
Added extensive logging for post-flip actions
Improved rotator timeout handling - now aborts alignment instead of waiting indefinitely
Reliability & Error Handling
More resilient INDI web manager connectivity checks with graceful failures
Fixed ADU-based flat frame signature matching
Improved filter offset handling for multi-camera setups
Better dark frame diagnostic logging
Other Fixes
Fixed comet position calculations for hyperbolic orbits (e.g., 3I/ATLAS)
Improved artificial horizon importer to handle spaces in files
Enhanced HIPS survey filtering and sorting with partial sky survey support. Support for many more catalogs like NSNS
KStars v3.8.0 is released on 2025.12.03 for Windows & Linux. MacOS release is expected in one week due to build issue on KDE CI infrastructure.
For Linux users, it's highly recommended to use the official KStars Flatpak hosted at Flathub. You can install the stable flatpak or try out new features by downloading the KStars Nightly Flatpak for x86_64 and arm64 architectures.
Live Stacker: LRGB Stacking
John Evans implemented generation of RGB and LRGB images from individual mono subframes. Watch R, G, B and optionally L directories and combine the individual stacks into RGB or LRGB images.
Add directories for R, G, B and optionally L subs. These are monitored and a single color image is displayed.
RGB images are combined with a Linear Fit type algorithm. LRGB images are combined with a LRGB Combination type algorithm. SNR algorithm has been rewritten. Appears to work better but is more resource intensive.
Live Stacker: ImageMM Stacking Method
John Evans added an implementation of the ImageMM stacking method. This implementation strikes a balance between speed (it needs to be a Live Stacker) and fidelity.
To use: select ImageMM as the stacking method and play with the available controls. This method is considerably more resource intensive than "regular" stacking because it uses an iterative approach.
Live Stacker: Live Stacker Monitor
John Evans implemented the Live Stacker monitor. Live Stacking Monitor window is a popup from Live Stacker that shows a table of subs that match the chosen directory in Live Stacker.
The purpose is to allow analysis of Live Stacker, for example to allow investigation of bottlenecks in the stacking process.
When a sub is added to the watched directory, the sub is added to the Monitor's table. As the sub is processed by each step of the process information is updated in the table:
Waiting to load. The sub is in the queue to be processed but Live Stacker is busy with other subs.
Loading. The sub is loaded into memory.
Plate solving. The sub is undergoing plate solving (if appropriate).
Waiting to stack. The sub is waiting to be stacked (e.g. currently there are insufficient subs loaded to start a stack).
Calibration. Dark / Flat calibration.
Alignment.
Stacking.
Table columns and sort order are configurable. Changing cells can be highlighted (or not)
Task Queue system
Observatory startup and shutdown steps are now replaced by the new highly configurable Task Queue system. The Task Queue System is a modern, flexible automation framework that replaces traditional startup and shutdown scripts with a template-based, configurable task execution system. It provides a visual interface for building sequences of automated operations that can control your observatory equipment through INDI. It is accessible from Ekos Scheduler.
Why use it? The Task Queue system offers several advantages over traditional scripting:
Visual Management: Build and monitor task sequences through an intuitive graphical interface
Reusability: Use pre-built templates for common operations without writing code
Error Handling: Built-in retry logic and configurable failure responses
Device Compatibility: Automatic matching of templates to available devices
Progress Monitoring: Real-time status updates and detailed execution logs
Collections: Pre-defined task sets for startup, shutdown, and other common scenarios
Flexibility: Combine templates or create custom variations without programming
Safety Monitor
KStars scheduler now fully supports INDI Safety Monitor driver released part of INDI v2.1.7. A standalone driver may be used (independent of the equipment profile) that is running on a different INDI server to provide 24/7 safety monitor updates to the scheduler. No observatory operations shall take place unless it is deemed safe by the safety monitor.
The INDI Safety Monitor can listen to any number of sources including weather stations, UPS (uninterruptible power supply) monitors, and any auxiliary device that support the INDI's standard SAFETY_STATUS property.
Push-To Assistant
Wolfgang Reissenberger added an incredibly useful tool for users with manual mounts: Push-To Assistant. Just attached a camera to your dobsonian and use this tool to center the target in the eyepiece. This tool assumes that both the camera center and eyepiece center are already aligned.
The new push-to assistant is intended as plate solving support for mechanical mounts in combination with a digital camera on a finder scope.
Setup: Create an optical train with the Telescope Simulator as mount and configure your combination of finder scope and digital camera.
Usage
Start Ekos
open the Push-to Assistant located in the Tools menu
move your scope as good as possible to the target you want to find
select the target from the catalog or enter its coordinates manually and press "Select target"
press "Solve position" to determine the position your scope is currently pointing at
as soon as the position has been solved, the assistant displays hints in which direction you should move your mount to be closer to the target
correct your mount position and press "Solve position" again
if you want to automatically repeat plate solving, configure the delay and press the "Repeat" button.
KStars v3.7.8 is released on 2025.08.13 for Windows & Linux. MacOS release is pending. It's a bi-monthly bug-fix release with a couple of exciting features.
Live Stacking
The moment many of you have been waiting for has arrived! John Evans has introduced the highly anticipated Live Stacking feature to Ekos, seamlessly integrated into the FITS Viewer. Once you configure your live stacking directory, any FITS images added will be automatically stacked in real-time.
This feature works independently of your existing sequences or scheduler sessions, allowing you to configure the live stacker to process captured images for an enhanced view of your final results. It's particularly valuable for public observatories and star parties, where real-time feedback can greatly enhance the viewing experience.
Since Live Stacking is still in beta, we welcome your feedback and suggestions for improvement. Check out the demonstration videos below to see the feature in action and learn about its capabilities.
Equipment Profile Editor
The Ekos Equipment Profile editor has received a complete redesign. We've eliminated the limitations of the previous editor—you can now add unlimited drivers to your equipment profiles without restrictions. Need three different mounts in a single profile? No problem!
Both driver and profile lists now include search functionality, making it quick and easy to locate specific drivers. This flexibility gives you unprecedented control over your equipment configurations.
Focus History Navigation
Wolfgang Reissenberger has added an invaluable Focus History navigation feature. When autofocus encounters issues, you can now navigate through your focus frame history to inspect images from all autofocus runs, making troubleshooting much more effective.
The Focus module now includes a dedicated navigation panel. To optimize screen real estate, we've moved the detected stars display and current HFR readings above the V-Curve rather than below it, freeing up valuable space.
To use this feature, simply configure the maximum number of stored frames in your Focus settings. The navigation controls are active only when autofocus sequences aren't running.
FITS Viewer Stretch Presets
Hy Murveit has refined the FITS Viewer stretch sliders and added a convenient preset button that cycles through seven different stretch configurations, offering various combinations of background brightness and contrast levels.
When you display the histogram and zoom in, the sliders provide much finer resolution control—particularly useful for precise black point adjustments.
Flatpak Support
Thanks to extensive collaboration between the Ikarus Technologies team, KDE Infrastructure team, and the Flathub community, we now offer both Stable and Nightly Flatpak packages.
The KStars Flatpak includes all INDI drivers and runs securely within the flatpak sandbox environment. This allows you to install both Stable and Nightly versions simultaneously without conflicts; perfect for testing the latest features and bug fixes while maintaining access to the stable release.
Hy Murveit improved the Polar Alignment algorithm, especially when it the mount is close to the meridian. Wolfgang Reissenberger improved the the size of the arrows indicating the direction of the necessary adjustments so they're more visible in the Polar Alignment Assistant.
Migration to Qt6
This release represents a significant technical milestone with our complete migration to Qt 6 and KDE Frameworks 6. KStars is still compatible with Qt 5 until all major distributions fully switch to Qt 6. While these changes happen behind the scenes, they provide a more robust foundation for future development.
The entire KStars development team contributed to this substantial effort. Special recognition goes to Eric Dejouhanet and Robert Lancaster, who invested countless hours reworking our complex CI/CD pipelines and macOS support builds in KDE's Craft system. This release wouldn't have been possible without their exceptional dedication.
KStars v3.7.6 is released on 2025.04.01 for Windows, MacOS & Linux. It's a bi-monthly bug-fix release with a couple of exciting features.
Scheduler Plans Visualized
Hy Murveit added a graph to the Scheduler page that displays visually the scheduler's plans--the same plans described in the log at the bottom of that page, and partially described in the scheduler's table. You can see altitude graphs for all the scheduler jobs, which are highlighted in green when that job is planned to be active. The next two nights of the plan can be accessed using buttons to the right (and left) of the graph. The graph can be enlarged or hidden by sliding the "splitter" handle above it up or down.
PHD2 & Internal Guider RMS
Many users reported differences between the RMS value reported by Ekos internal guider vs PHD2. This is not a new issue as there was a difference in RMS calculations ever since Ekos Guider module was developed over a decade ago. In this release, we updated the internal Guider RMS calculations to use the same algorithm used by PHD2. This way, there is now a more consistent metric to judge the performance of the two guider systems.
Weather Scheduler Integration
Weather station integration with the scheduler was improved. The weather enforcement is now global and not per job. If weather enforcement is enabled, you can adjust the Grace Period (default 10 minutes) in cases where the scheduler cannot be started due to a weather Alert or Warning.
When a weather warning is received, existing jobs can continue to execute but new jobs will not be executed until the weather situation improves. Upon detecting a weather hazard, the scheduler execute a Soft shutdown mode where it can park the mount and dome, but still retains connection with INDI drivers to continue monitoring the weather situation. If the weather does not improve by the Grace Period, it then commences a full shutdown of the observatory. Otherwise, it should resume the job from where it was left.
Contrast Based Focusing
John Evans added an option to allow focusing on non-star fields by using various contrast based algorithms. This is suitable for Lunar, Solar and planetary imaging.
Autofocus Optimization
John Evans added an option has been added to Focus that allows an Autofocus run to re-use a previous successful Autofocus result if the previous AF run occurred within a user-defined time period, say <10mins ago. This can speed up certain situations when using the Scheduler where multiple Autofocus requests can happen within a short period of time.
Imaging Planner Improvements
Hy Murveit pushed a new Imaging Planner catalog release along with improvements to the KStars Imaging Planner.
It should now start up much more quickly on first use, or first use after a catalog upgrade.
There were stability improvements.
The catalog was extended to include 770 objects.
Upgrade to KStars 3.7.6, use Data -> Download New Data to get the latest Imaging Planner catalog, and run Load Catalog in the Imaging Planner tool to take advantage of all these improvements.
Quick Go & Rotate
Added support to Go and Rotate in Framing Assistant. This would command fast go to target and then followed by rotation to match position angle indicated. Simply adjust the Position Angle to your desired angle then command Ekos to solve and rotate in one go.
Scheduler Coordinates Flexibility
Wolfgang Reissenberger introduced enhancements for handling target coordinates in the scheduler module:
Add an option to switch the target coordinates between J2000 and JNow. This is interesting for those cases where the user wants to enter the coordinates manually, but has the coordinates only in JNow - for example when taking them over from the align module.
Add a "use the current target" button. Currently, there is only an option to take over the current skymap center.
Furthermore, during the time where the moon is visible, it should be possible to schedule only those jobs that are not disturbed by moonlight (e.g. H-alpha captures). To enable this, a new optional constraint is introduced where the maximal moon altitude could be set.
Use PHD2-scheme graph
Toni Schriber modified the internal guider chart to use PHD2-scheme (RA/DEC) for graph of guide mount drift. This should help comparisons between PHD2 and internal guider more consistent.
KStars v3.7.5 is released on 2025.02.03 for Windows, MacOS & Linux. It's a bi-monthly bug-fix release with a couple of exciting features. Here are the release notes organized by developer.
Jasem Mutlaq
Added dome slit visualization on sky map. Specify the Dome Measurement parameters in the INDI Dome driver to see a live dome slit overlay in the Sky Map.
Implemented generic DBus methods for KStars options
Added SchedulerSleeping event
Added mutex protection for multi-threaded resources
Enhanced scheduler loading and settings management
Improved filter manager operations
Fixed video subframing. Up to 50x improvement in subframed video feeds.
Fixed multiple profile editor issues
Added VSCode development setup support
Hy Murveit
Fixed DMS delta angle calculation
Added mandatory settle to PAA
Improved imaging planner stability
Fixed pierside placeholder directory usage
Added START_AT scheduler test
Fixed Abell planetary nebula lookup
Enhanced PAA adjustment estimation
Wolfgang Reissenberger
Implemented video sequence capture. Preliminary support for capturing Video files as regular sequences in the Capture module. Great news for EAA.
Fixed focus options
Improved remote directory handling
Fixed flats with wall position
Enhanced filter wheel integration
John Evans
Enabled focuser controls when camera disconnected
Improved focus measure framing
Fixed focus advisor code warnings
Updated aberration inspector functionality
Toni Schriber
Fixed overshooting cosine in CachingDms calculation
Implemented calibration reuse after rotation. Guide calibration data can now be re-used between sessions after rotation.
Ben Cooksley
Removed CMake trace/debug logs from CI runs
György Balló
Set window icon
Oliver Kellogg
Fixed typo in FITS Viewer configuration
Akarsh Simha
Fixed right-click popup menu on deep stars
Technical Highlights
Improved capture sequence stability: Set 5-minute timeout for transient operations (dome motion, mount parking/unparking, dust cap operations, focusing, filter wheel changes) to prevent indefinite sequence stalling.
Improved mount rotation processing
Enhanced scheduler loading mechanism
Added mutex protection for multi-threaded resources
KStars v3.7.4 is released on 2024.12.05 for Windows, MacOS & Linux. It's a bi-monthly bug-fix release with a couple of exciting features.
Imaging Planner
Hy Murveit added a brand new Imaging Planner in KStars to facilitate imaging.
The Imaging Planner tool helps users choose which objects to image. Users can download catalogs of recommended objects, or possibly create and share their own catalogs. The tool computes when the objects in a read-in catalog may be imaged on the selected night given constraints such as minimum altitude, terrain and moon separation.
It can sort the objects along several different dimensions including the number of hours an object may be imaged tonight (given the users geography, constraints and possibly artificial horizon), its peak altitude, distance from the moon, constellation, name and type. Objects can also be filtered out for several reasons (e.g. type of object, whether it was previously imaged, keywords the user has added, whether the object has been selected, user not interested, etc).
This tool helps users research the objects by showing small images of the objects, showing the objects' sky locations on the skymap, and by providing links to follow to internet sites with more information and images. It allows users to attach notes and links to objects, and select certain of them for further consideration. This tool can be used in conjunction with the Ekos imager or any other imaging tool. It does not currently directly interact with the actual imager; it only helps the user decide what to image.
Simbad Integration with FITSViewer
John Evans added a new, experimental feature to the FITSViewer that allows the user to dynamically query the SIMBAD astronomical database and highlight the results on the image in the FITSViewer. The user draws a circle on the image and the objects within that circle are then displayed in a table and on the image.
It is possible to filter by object type and click through to the Simbad / CDS or NED websites for more information about the objects.
This is an interesting tool to see what is in your image, be it a subframe whilst you are imaging or a completed image that you have reloaded into the FITSViewer.
In order to use the feature you will need an internet connection to access the online Simbad database and an image must have WCS enabled within the FITSViewer. For the most accurate results, plate solve the image with the build-in FITSViewer plate solver. The feature is controlled by a toggle in the FITSViewer options.
New Focus Measures
John Evans introduced a new contrast based focusing algorithm suited for solar and planetary imaging.
4 new focus measures have been added to the Focus Module to complement the existing measures of HFR, FWHM, etc. · StdDev. This is similar conceptually to the Fourier Algorithm but is simpler. It uses an algorithm based on the standard deviation of the pixels in the image as the measure of focus. It can be used on star fields. · Contrast based measures use algorithms that can be found in other areas of image processing and uses the contrast of texture in the image in various way as a measure of focus. The following measures are available:
o Sobel o Laplassian o Canny
These measures require some form of extended object in the image so will not work on star fields. They are intended for Solar, Lunar and planetary focusing.
These algorithms can be used on the whole image or with the existing mask features, or with a user-defined region-of-interest that is used in single-star mode for star based focusing measures.
This new feature requires the openCV library to be installed (a standard installation is fine). This library is not installed by default with Kstars so anyone wishing to use these features will need to first install openCV and then rebuild Kstars on their system. It will not be available with pre-built executables.
KStars v3.7.3 is released on 2024.10.03 for Windows, MacOS & Linux. It's a bi-monthly bug-fix release with a couple of exciting features.
Extension Interface
Ed Lee contributed the Extension Interface for KStars.
Extensions are small programs that can be added to interact with KStars/Ekos/INDI in order to provide extra functions and features. Extensions are separate from KStars. They are not provided as part of this software. Only a means to call them is provided for convenience. Make sure that you understand the requirements and risks of using an extension.
FireCapture launcher (FC_launcher): disconnects the current primary camera INDI driver and launches FireCapture. Upon close restarts the INDI driver.
KStars Backup (KS_backup): provides a GUI for the archiving and restoration of KStars/INDI (and optionally others) configuration directories to/from .tar.gz archives/
Sirial_EEA: provides live stacking of the preview job from the Capture Module and displays it auto-stretched in the Ekos preview window.
Each extension must have a companion configuration file also located in the extensions directory, named the same as the executable with the addition of a .conf eg: an extension named example must also have a configuration file named example.conf A configuration file is a plain text file that provides configuration settings to the extension program and usage information to the user. A configuration file is only valid if it contains a line starting with: minimum_kstars_version=x.y.z The x.y.z is the minimum release of KStars that the extension is designed/tested against. This value is checked against the current KStars KSTARS_VERSION macro defined in version.h and must be equal or lower for the extension to be considered valid. The extension should also check that this minimum_kstars_version string matches what it expects.
Optionally each extension can also provide an icon file for display in the Extension drop down list. Again the naming should match the extension executable with a valid file extension (.jpg, .bmp, .gif, .png or .svg) and be placed in the same extensions directory. A default icon is used for any extension that does not provide it's own icon.
Several new DBus functions/signals are added to enable general extension use and for a specific upcoming extension.
Multi-Target Scheduler
Wolfgang Reissenberger continued the development of multi-camera acquisition and now scheduling with many exciting updates!
Multi-Camera Scheduling
With this new release it is possible to create and run schedules for two or more optical trains in parallel within the same KStars instance. All mount related events like slewing, dithering, alignment and meridian flip are synchronized, i.e. capturing on all optical trains takes these events into account.
Lead and follower jobs
If you want to run capturing on multiple optical trains in parallel, you need to decide, which of the optical trains is the lead job, which defines the target and the scheduling criteria. All other optical trains will be follower jobs, for which only the capture sequence to be used is relevant.
Job Synchronization
Ekos ensures that no mount motion happens while one of the optical trains is capturing to avoid star trails.
In case of dithering, the capture module decides what to do as soon as dithering is requested, depending on the setup of the lead job. If the remaining capture time of a follower train is more than 50% of the lead job exposure time, capturing of the follower train is stopped and restarted after dithering. If the remaining capture time is less than 50%, the Capture module waits for the follower to finish its capture.
For the meridian flip and re-alignment: both are controlled by the lead job. All running follower capturing sequences are stopped and restarted after a successful completion of the respective action.
Recommendations
The lead job should have the longest exposure times, especially if dithering is used.
If you use re-focusing, consider to not suspend guiding during focusing, since the other optical train might capture in parallel.
Configure the same optical train in the Align module that you use in the lead job. This is important if you use the re-alignment check option of the scheduler.
Do not use the Force re-alignment before re-starting jobs, since each new iteration of the lead job stops capturing of the follower trains. Consider using Verify captured image position every n frames instead, since this option triggers re-alignment only if it is necessary.
Adhoc focus with Multi-Camera setups
Wolfgang Reissenberger added support for simultaneous parallel focusing when you are running multi-camera setup. It would be a good idea to disable Suspend Guiding so that guiding is unaffected when focusing operation commences.
Invent Multi-Star Guide Star
Hy Murveit introduced an experimental Multi-Star parameter. In the original (conservative) multi-star guiding implementation, although many stars contributed to the computed guiding drift computation, there still was one more important star that anchored the scheme.
With this change, all the guide stars contribute equally to the guiding calculations. This removes the risk that an unfortunate selection of a double star for the more-important main guide star would degrade performance.
