KStars 3.6.8 is Released

KStars v3.6.8 is released on 2023.12.03 for Windows, MacOS & Linux. It's a bi-monthly bug-fix release with a couple of exciting features.

Aberration Inspector

John Evans introduces the very exciting Aberration Inspector tool. The Aberration Inspector is a tool that makes use of Autofocus to analyze backfocus and sensor tilt in the connected optical train. It solves up to 9 virtual tiles on the sensor as defined by the existing Mosaic Mask.

The information is then used to analyze:

• Back focus.
• Sensor Tilt.

There are 4 sections:

• V-curve for the each tile.
• Table of data detailing the curve fitting results.
• Analysis of back focus and tilt.
• 3D Surface graphic to explain the Petzval Surface intersection with the sensor.

This release provides display only functionality. In future it would be possible to add functionality to offer recommendations for adjustments using Octopi, PhotonCage, etc.

Sub-exposure Calculator

Joseph McGee continues to add improvements and fixes for the Sub-exposure calculator. For usability, the window is now re-sizeable, an issue with the display of tool tips was corrected, and an indicator has been added for the sensor type of the selected camera (Mono / Color).  For functionality: the upper limit of the Noise Increase input parameter was increased, support was added for cameras with non-variable read noise, (cameras with CCD sensors).

Several new camera data files were added to the KStars source code repository, and a function to allow direct direct download of camera files from the repository was enabled. (Note: users who have created their own camera data files, may wish set the file attribute to read-only, and/or make a back up copy in case of an accidental over-write from the download function if the camera file has the same name).

A new experimental graphical tool to determine an appropriate number of sub-exposures for integration was added. This tool allows the selection of an exposure time to noise ratio for a stacked image; the tool will compute the number of sub-exposures required to achieve that value.

Added several new camera data files:

• Atik-16200CCD_Mono.xml
• FLI-16200CCD_Mono.xml 
• QHY_CCD_294M_Pro.xml
• QHY_CCD_461_PH.xml
• QHY_CCD_163C.xml 
• QHY_CCD_163M.xml
• QHY_CCD_268C.xml
• QHY_CCD_294M.xml
• QHY_CCD_600_PH.xml
• ZWO_CCD_ASI294MC
• Pro.xml ZWO_CCD_ASI294MM
• Pro.xml ZWO_CCD_ASI533MC
• Pro.xml ZWO_CCD_ASI2600MC
• Pro.xml ZWO_CCD_ASI6200MC
• Pro.xml ZWO_CCD_ASI533MC
• Pro.xml ZWO_CCD_ASI533MM
• Pro.xml Nikon_DSLR_DSC_D5100_(PTP_mode).xml Nikon_DSLR_DSC_D700_(PTP_mode).xml

FITSViewer Solver

Hy Murveit added a very useful feature to the FITS Viewer: a built-in solver!

The FITS Viewer Solver is used to plate-solve the image loaded in the FITS Viewer's tab. It only works with the internal StellarSolver. You get the RA and DEC coordinates for the center of the image, the image's scale, the angle of rotation, and the number of stars detected in the image. Its main use case is debugging plate-solving issues in Ekos, though the information displayed can be generally useful. The controls and displays are described below.

This adds a new tool inside the splitter on the FITS Viewer. It plate-solves the displayed image, and allows the user to experiment with a number of plate-solving parameters, and thus help debug plate-solving issues.

How to test it out?

• Open the sliding panel on the left part way, click on Plate Solving, and resize the windows appropriately.
• Experiment with the parameters available (Use Scale, Use Position, the scale and RA/DEC positions, choose a profile and/or edit it)
• Click Solve, and the image is solved and the solution presented in the Scale and RA & DEC and Angle boxes.
• If you enable "Mark Stars" above the image window, you will also see the stars that were detected.

Quality of Life improvements

• Make "Set Coordinates Manually" dialog more intuitive.
• Telescope name specified in the optical trains are now saved in the  FITS header (the mount name was saved before).
• New placeholders for ISO, binning and pure exposure time added.
• Add a new not-default scheduler option to disable greedy scheduling.
• Reduce latency between captures, especially when guiding / dithering.
• Fix issue with differential slewing.
• Separate Business Logic from UI in Scheduler.
• Fix bug in estimating job time, capture delays were misinterpreted.
• Fixed guide start deviation was not saved properly in esq file.
• Bugfix in one-pulse dither. Dither pulses were going the wrong way.
• Fix Scheduler hangs when Focus does not signal Autofocus start failure.
• Focus Guide Settle Bug.

KStars v3.6.7 is Released

KStars v3.6.7 is released on 2023.10.03 for MacOS & Linux. Windows build is still pending and should hopefully be released by 10th of October. It's a bi-monthly bugfix release with a couple of exciting features.

Image Overlay Component

Hy Murveit introduced a long requested feature: Custom Image Overlays!

With this new feature, a user can add their own processed/completed astro-images, and the system will display them scaled and rotated appropriately on the Sky Map.

The feature is controlled in the KStars Settings menu, in a new tab labelled Image Overlays. First the user needs to add files into a directory, parallel to the logs directory, called imageOverlays. Simply add the images there (typically jpegs). Ideally these aren't massive files for performance reasons, but probably width 1000 or 2000 are fine. I have been testing with larger files, which will also work be use more system resources on slower CPUs.

The user then uses the Image Overlays menu in KStars Settings to (one-time) plate-solve the images and check a box to enable the image display. Successful plate-solve info is stored in the user-db so that it doesn't have to be done again. The images should, from then on, appear in the SkyMap in the proper position. There is a way to easily navigate to the images without manipulating the SkyMap by selecting a row in the overlay table and clicking on the "Show" button. You can move from one image to the next with up/down arrow keyboard commands.

A user can adjust the plate-solve timeouts. As these are mostly blind solves (jpegs won't have any header info, and as currently implemented, no header info is used) the plate solving can be problematic. You can choose a default image scale (arcseconds-per-pixel) or leave that to 0.0 to not use scale. If there are files that won't solve, the user can add RA,DEC into the image's row in the table displayed, which would get the solver to use the sky position as a constraint. The user can also add the scale that way. In fact, if the user knows all the info for the image, he/she can populate all the fields on the image's row and simply set the status field to OK, and plate-solving would no longer be required.

Rotator Dialog Improvements

Toni Schriber continued simplifying the Rotator Dialog. Rotator Flip Policy was introduced. This (global) policy is an answer to this question and to this wish. It's now possible to define how the rotator reacts after a flip or if the result of a solved reference image reports a different pierside respective to the actual mount pierside. Preserve Rotator Angle will keep the rotator position and the camera is virtually rotated by 180°. Preserve Position Angle will keep the camera position angle.

The rotator always turns the camera to the original position angle and the image will show the original star arrangement. Flip Policy can be altered in the StellarSolver Options under Rotator Settings.

More File Placeholders

Due to popular demand, Wolfgang Reissenberger added support for camera temperature %C, gain %G, offset %O and pier side %P.

This is not only applicable to locally captured images, but also for images captured on a remote INDI server.

KStars v3.6.5 is Released

 

KStars v3.6.5 is released on 2023.06.01 for MacOS, Linux, and Windows. It's a bi-monthly bugfix release with a couple of exciting features.

Sky Map Rotation

Akarsh Simha added a new feature to allow the user to rotate the sky map. It also allows some standard settings like inverted view. Here are some the highlights:

1. Rotate the sky-map freely: Shift + mouse drag on the sky map
2. Pick pre-defined orientations: Zenith Up / Zenith Down / North Up / North Down depending on the coordinate system being used
3. A magic mode for Dobsonians: The Erect Observer Correction feature, when selected along with Horizontal Coordinates / Zenith Down settings, will reproduce the orientation seen in the eyepiece of a Dobsonian. May need a one-time adjustment for your specific Dobsonian using the shift + drag feature.

Optimal Sub-Exposure Calculator

Joseph McGee made his first contributor to KStars with the Optimal Sub-Exposure Calculator. This is the first iteration of the calculator and only a handful of camera profiles is supported. There are different points of view within the astrophtography community on how optimal sub-exposure should be calculated and whether we should consider other factors such as processing time given the volume of data produced. Your feedback would be appreciated on this first iteration of the calculator.

Implementation of an optimal sub-exposure calculator based upon the work of, and presentation by, Dr Robin Glover. The calculator considers multiple inputs to determine a sub-exposure time which will provide minimal overall noise in the image:

• A sky quality measurement (SQM) for light pollution
• The optic focal length
• A filter bandwidth
• Camera read-noise (based upon gain/iso)
• An optional adjustment to the allowable increase in noise from light pollution

As inputs are adjusted the calculator will refresh graphic presentation of potential exposure times of the range of gains, and update calculated outputs. The output values are separated into two sections: one for the sub-exposure, and another for image stacks of various integration times.

The sub-exposure outputs are:

• the optimal sub-exposure time
• the count of electrons produced from light-pollution
• the shot noise, (noise from light pollution)
• the total exposure noise, (the combined noise from light-pollution and camera read-noise)

The image stack information is presented in a table showing:

• planned integration hours
• the count of exposures to reach the planned integration hours
• the actual stack (integration time) in seconds
• the noise for the stack
• a ration of stack time to noise, (as a indicator of quality)

An instance of the sub-exposure calculator can be started from a new 'clock' icon on the ekos capture screen. Multiple instances of the sub-exposure calculator can be started concurrently so that side-by-side comparisons can be made for variations in inputs.

Data for camera read-noise will be provided through individual xml files which will be user maintained and published in a repository. These camera data files persisted within a folder "exposure_calculator" under user/local/share/kstars. The calculator includes the capability to download camera files from a repository. Upon the initial start of the calculator at least one camera data file download will be mandatory before the calculator can be instantiated.

The intent is that camera data file names will be used to allow the calculator to select an appropriate camera data file based upon the device id of the active camera. (But some of the initial camera files were named using educated guesses, and will likely need to be re-named).

Rotator Dialog Improvements

Toni Schriber merged improvements and fixes for the Rotator Dialog. As shown in the illustrations the user interface is very simple and there is only one parameter to set: The Camera Position Angle. It is a very consistent term and easy to understand. The same Position Angle (PA) is also used in Alignment, Scheduler, and the Sky Map.

In the gauge this angle is presented in the same color as the FOV in the planetarium sky and in viewing direction. This way one can relate and understand this angle intuitively. The rotator angle is presented in gray and also in viewing direction. This angle is calculated from the Camera PA and the Cameras Offset Angle which is calibrated each time a [Capture & Solve] or a [Load & Slew] is brought into action. For further clarity the rotator angle and the camera offset is displayed again in a information window together with the current pier side.

The Rotator Settings can be accessed either in the Capture or Align modules.

Focus Linear 1 Pass Improvements

John Evans continued his phenomenal improvements to Ekos Focus module with L1P Phase 2 changes as detailed in the Linear Focus Phase 2 document. Here are the highlights:

1. Optimized curve fitting . Should be faster and more accurate and includes outlier rejection.
2. Currently HFR is the only fitting "measure" available. The following have been added: a) HFR Adj (adjusted HFR to compensate for star brightness vs background variation) b) FWHM c) Number stars (max at focus rather than a min) d) Fourier Power (alternative focus method not requiring star detection)
3. Focus units can be displayed in pixels or arc-seconds.
4. Critical Focus Zone - a calculator with 3 different algorithms has been added
5. Focus Offset Utility to automatically build focus offsets.
6. Take flats at same focus point as lights has been fixed.
7. Focus Adviser. Still working on this but a tool to help with focus parameters (since there are now so many).
8. SEP parameters suggestions for focus. Keen to get some feedback on this.
9. Adaptive focus to adapt the focuser position between Autofocus runs, aiming to keep optimum focus for each sub-frame. Adaptations for Temperature and Altitude are supported.
10. Adaptive focuser start . The starting position for an AF run can be filter and Adaptive Focus adjusted.
11. Focus walks added to control how the inward sweep of the AF process performs.
12. AF Overscan originally implemented in the Linear algorithm and then reused by Linear 1 Pass now extended to all focuser movements.

In addition to HFR, you can now use different measurements (FHWM, # of Stars, Fourier Power) that may work well with your setup and environment. Here are some focus runs with each of the new measurements types. You will notice that the solutions are very close to each other.

FWHM

# Of Stars

Fourier Power

Focus Aberration Inspector

Wolfgang Reissenberger introduced the mosaic view well known from PixInsight's AberrationInspector script that builds a mosaic from all image corners and center tiles such that they can be compared directly.

Supernovae are back

The last few releases was missing supernovae data since the online source that was providing the data decided to go offline. Thankfully, Philipp Auersperg-Castell communicated with the fine folks over the Transient Name Server (IAU Supernovae Working Group) to obtain daily supernovae updates and imported them to KStars. All Recent supernovae should be available now in KStars.