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 v3.5.2 is is released on March 1st, 2021 for Windows, MacOS, and Linux. This release incorporates significant improvements to Ekos Polar Alignment Tool in addition to supporting manual rotations in the Alignment Module.
Brodrick Basshamadded a manual rotation dialog to the Alignment module in Ekos for Load & Slew. Now users without motorized rotators can adjust their camera manually in order to achieve the desired frame orientation. Check the video below for a demonstration of this feature.
Hy Murveit contributed major improvements to Ekos Polar Alignment Assistant. There are two major changes to Ekos' semi-automated polar alignment scheme:
Polar Alignment may now be performed while pointing anywhere in the sky. Thus, for example, if a tree is blocking your view of the pole, you can still polar align.
The user interface has been adjusted. As before, you select a star to help you adjust your mount's altitude and azimuth settings. Ekos now displays a triangle, and you move your selected star (which is circled) over the yellow line to adjust your altitude, and then over the purple line to adjust your azimuth. While you're doing so, if you have "Update PA Error" checked, the system estimates the remaining polar-alignment error.
Eric Dejouhanet fixed a few issues in Focus module including restart and detection of disconnected focusers. Furthermore, a number of issues detected by Coverity scans (MR 214 & 216) were addressed in this release.
To reduce memory footprint on device with low resources, an Adaptive Sampling option was introduced to conserve memory when displaying images in the FITS Viewer. It checks the available memory and performs on-the-fly downsampling of images to reduce memory consumption. This only affect the display and not the actual data.
Just in time before the next total lunar eclipse of 2018, KStars v2.9.7 is out for Windows, Linux, and MacOS.
This is a feature-rich release while still continuing on making KStars more resilient and reliable.
MacOS improvements
Robert Lancaster diligently worked to improve INDI driver support on MacOS while adding a new FFMPEG-based Web Camera driver that can even records videos streamed directly from your phone. Furthermore, drivers from SBIG, MGEN, ATIK, INDuino, SSAG, Morovian, Fishcamp, and Radio Detectors have been migrated successfully to MacOS. Peter Polakovic graciously offered assistance in the SSAG and ATIK migrations.
With INDI Webcam driver on MacOS
Robert Tricking Star Detection Algorithm!
Ekos Scheduler
Eric Dejouhanet & Wolfgang Reissenberger contributed significantly to the Ekos scheduler to improve its behavior under a number of scenarios. As a result, the scheduler is now more user-friendly and quite straight forward to setup and monitor progress. More work is pending for the next release to further enhance the scheduler.
Planning Sadr Mosaic with Scheduler
Polar Alignment Assistant
The PAA tool received few improvements to simplify the process, it's now literally a 1-button click operation.
Ekos Live
Support for EkosLive is added in this release. EkosLive is a real-time web application that communicates with Ekos via websockets to provide a feature-rich yet simple interface to control and monitor all the observatory equipment. Backed by Cloud services for storage, users can store their images on the cloud and access them at any time and from anywhere. Thanks to the rich metadata system that ships with EkosLive, it is very easy to search and categorize your astro images.
EkosLive is currently in Beta.
Custom Drivers
Long requested by the community, KStars now offers an easy method to add INDI custom drivers. This is perhaps more important to users who have multiple devices and want to distinguish them. Suppose you have two SBIG cameras and want to use them simultaneously with Ekos. Currently, there is no way to do this out-of-the-box. You need to manual create an alias by copying over the SBIG XML file under /usr/share/indi, and then rename the label to be able to use a different alias.
With the Custom Drivers dialog, it's now quite straight forward to create any alias for any driver. After a restart, you can see the new alias in the Profile Editor. Moreover, this feature also works with INDI Web Manager, so you can create aliases for remote drivers as well!
Here are more highlights:
+ Support for loading compressed FITS (*.fits.gz) in FITS Viewer.
+ Android fixes + improvements by GSoC 2018 student Csaba.
+ Disabled internet check for online astrometry solver to workaround Qt bug.
+ Fixed PHD2 file not found issue.
+ Added option to restart alignment process in scheduler in case of calibration failure.
+ Support for manual dither plus dithering to a specific X,Y location.
+ Support for Auto Park Timer in Mount Module.
+ Support for Remote Drivers in the Profile Editor.
+ Added video exposure duration control to the Video Stream window.
When setting up a German Equatorial Mount (GEM) for imaging, a critical aspect of capturing long-exposure images is to ensure a proper polar alignment. A GEM mount has two axis: Right Ascension (RA) axis and Declination (DE) axis. Ideally, the RA axis should be aligned with the celestial sphere polar axis. A mount's job is to track the stars motion around the sky, from the moment they rise at the eastern horizon, all the way up across the median, and westward until they set.
In long exposure imaging, a camera is attached to the telescope where the image sensor captures incoming photons from a particular area in the sky. The incident photons have to strike the same photo-site over and over again if we are to gather clear and crisp image. Of course, actual photons do not behave in this way: optics, atmosphere, seeing quality all scatter and refract photons in one way or another. Furthermore, photons do not arrive uniformly but follow a Poisson distribution. For point-like sources like stars, a point spread function describes how photons are spatially distributed across the pixels. Nevertheless, the overall idea we want to keep the source photons hitting the same pixels. Otherwise, we might end up with an image plagued with various trail artifacts.
Since mounts are not perfect, they cannot perfectly keep track of object as it transits across the sky. This can stem from many factors, one of which is the mis-alignment of the mount's Right Ascension axis with respect to the celestial pole axis. Polar alignment removes one of the biggest sources of tracking errors in the mount, but other sources of error still play a factor. If properly aligned, some mounts can track an object for a few minutes with only deviation of 1-2 arcsec RMS.
However, unless you have a fancy top of the line mount, then you'd probably want to use an autoguider to keep the same star locked in the same position over time. Despite all of this, if the axis of the mount is not properly aligned with the celestial pole, then even a mechanically-perfect mount would lose tracking with time. Tracking errors are proportional to the magnitude of the misalignment. It is therefore very important for long exposure imaging to get the mount polar aligned to reduce any residual errors as it spans across the sky.
Several polar-alignment aids exist today, including, but not limited to:
1. Polar scope built-in your mount.
2. Using drift alignment from applications like PHD2.
3. Dedicated hardware like QHY's PoleMaster.
4. Ekos Legacy Polar Alignment tool: You need to take exposure of two different points in the sky to measure the drift and find out polar error in each axis (Altitude & Azimuth)
5. SharpCap Polar Alignment tool.
Out of the above, the easiest to use are probably QHY's PoleMaster and SharpCap's Polar alignment tool. However both software are exclusive to Windows OS only. KStars users have long requested support for an easy to use Polar Alignment helper in Ekos leveraging its astrometry.net backend.
During the last couple of weeks, I worked on developing Ekos Polar Alignment Assistant Tool (PAA). I started with a simple mathematical model consisting of two images rotated by a an arbitrary degree. A sample illustration of this is below:
Given two points, we can calculate the arc length from the rotation angle, and hence the radius. Therefore, it is possible to find two circle solutions that would match this, one of which would be the mount's actual RA axis within the image. Finding out which solution is the correct one turned out to be challenging, and even the mount's own rotation angle cannot be fully trusted. To be able to uniquely draw a circle, you need 3 points. So it was suggested by Gerry Rozema, one of INDI venerable developers, to capture 3 images to uniquely identify the circle without involving a lot of fancy math.
Since it relies on astrometry.net, PAA has more relaxed requirements than other tools making it accessible to more users. You can use your own primary or guide camera, given they have wide-enough FOV for the astrometry solver.
Moreover, the assistant can automatically capture, solve, and even rotate the mount for you. All you have to do is to make the necessary adjustments to your mount.
The new PAA works by capturing and solving three images. It is technically possible to rely on two images only as described above, but three images improves the accuracy of the solution. After capturing each, the mount rotates by a fixed amount and another image is captured and solved.
Since the mount's true RA/DE are resolved by astrometry, we can construct a unique circle from the three centers found in the astrometry solutions. The circle's center is where the mount rotates about (RA Axis) and ideally this point should coincide with the celestial pole. However, if there is a mis-alignment, then Ekos draws a correction vector. This correction vector can be placed anywhere in the image. Next the user refreshes the camera feed and applies correction to the mount's Altitude and Azimuth knobs until the star is located in the designated cross-hair. It's that easy!
Ekos PAA is now in Beta and tests/feedback are highly appreciated.
