Ron,

Thanks. It got the new test program running in Windows. Looks all okay. Solves all in a few seconds. The default option and "all stars" seems most reliable.

Han

Read More...

Hello Rob,

Thanks for the update. I wanted to test the Windows version 1.5 but failed to find the correct executable. There are 121 executable files but none with a name like Stellarsolver.exe or something similar. How to run this tester?

Han

rlancaste wrote: We haven't made any updates in several days, StellarSolver is now working very well in KStars, and things mostly seem stable. So I made a StellarSolver Release! It has been awhile, the last release was in May, but I took a break for a few months, and then this fall we were working very hard on the integration into KStars and making lots of changes, so I didn't want to make a new release until everything seemed pretty good. Here it is with the Tester built on Mac and Windows:

github.com/rlancaste/stellarsolver/releases/tag/1.5



Read More...

The just released ASTAP solver 0.9.449 (development version) is faster for small fields-of-view. This was achieved by creating an own star database cache and reusing the star data if possible. Improvement for small fields (<0.5 degrees) is 35 to 40% and a few degrees offset or more. For larger fields-of-view the improvement is less.

Released as development version at:
www.hnsky.org/astap_amd64.deb


Performance on some test images with a large position offset:
FOV=4.6 degrees, offset 50 degrees. Image solved in 2.6 seconds
FOV=0.48 degrees, offset 22 degrees. Image solved in 34 seconds
FOV=0.23 degrees, offset 6 degrees. Image solved in 20.5 seconds

Mac and Raspbian Pi versions will be released in a few days after more testing. Feedback is welcome

Han

Read More...

Extracting very faint stars is not easy, but important for solving. I think ASTAP performs very simular as Sextractor. Having SEP internally will be from programmers point of view a superior solution but see how ASTAP performs :)

Read More...

rlancaste wrote: _________
Source Extraction: to find the stars in your image in order to solve. In StellarSolver, I have the option for 3 different methods:

- Internal SEP: this requires no external programs, it is the same SEP star extraction algorithm we have used in KStars for Focus and Guiding for awhile now. It is essentially a library version of the method below (though there are some differences which is why they give slightly different results). It is entirely internal to the program, so there are no files saved to disk for the extraction which is great for Raspberry Pis etc.

- External Sextractor: this does require an external program, SExtractor, or the Source Extractor. This is their official standalone program. The drawback is you would need to have sextractor installed and it does save a bunch of files to disk in order to do its operations.

- BuiltIn Sextractor: This uses whatever method of source extraction the solver uses by default. StellarSolver uses SEP, just like the Internal SEP setting. Local astrometry.net uses its own source extraction method which uses a bunch of external resources including python, netpbm and other packages. (All those external dependences caused me huge amounts of headaches years ago when I ported kstars to Mac computers) And finally ASTAP has its own internal source extractor which is pretty good.

Note: Either Internal SEP or External Sextractor should be superior to the built in version of the programs. SExtractor is REALLY good at extracting stars, and that greatly speeds up solving, but it has a LOT of options that we need to perfect.

______________________________________

Rob


If there are still problems with star extraction you could consider the ASTAP v0.9.442 extraction option . For an other problem I have added the option to write the extracted stars to a comma separated csv file:

-extract snr_minimum

The snr_minimum is the minimum star snr value required. Default at 30 but for solving snr=10 should be used. The output file has the same name as the image but with extension .csv and is containing the following comma separated data as below:

It is a development version compiled for Linux and Windows. Mac and Raspberry Pi are outstanding.

Han


Read More...

rlancaste wrote: In reference to your our discussion about taking results from sextractor into ASTAP,

So the output of sextractor is just a binary fits table (It can also do ASCII, but astrometry.net didn't want to read those files). The column headings are very specific just to let you know. For example, the X position of a star has the heading X_IMAGE. And likewise for the other headings that I mentioned to you before.

I can certainly combine the data returned by sextractor with the data currently in the image buffer and save that as a FITS file with the appropriate FITS headers as you mentioned. But that would mean that a user would have to use my program in order to produce a file acceptable for ASTAP, since this would be a brand new format basically.

Part of the appeal of reading in an XYLS file and the options the way it works in astrometry.net would be the flexibility. A user could use sextractor, SEP, or maybe even astrometry.net to get the star info from an image. Then they could send that information directly to ASTAP to solve. They wouldn't need my program to do this because the format would already be compatible.

Obviously, ultimately, whichever way you want to accept the information into ASTAP would be fine with me, since I'm just making an interface for all these solvers and I've already had to make a number of adaptations to accommodate the differences between them. I definitely do understand the appeal of having the image data come along with the table of information. So, I can do it your way if you like.


For the record, ASTAP can still read and display these XYLS files but in the next ASTAP version 0.9.410, I will remove the possibility to use them as an input to the ASTAP solver. At the moment I don't think this option will be ever used. I like to clean up the ASTAP code and secondly the ASTAP source extractor is also improved making sextractor usage less desirable.

Han

Read More...

Hello Robert,

What's next for the StellarSolver?

Han

Read More...

The ASI533 camera your using has a native resolution of 3008x3008 pixels which would result in a square FOV. But the manual is also speaking of 1920x1080 pixel mode. So the question is which binning mode is used?

Read More...

wadeprunty wrote: ***A side note: ASTAP works for me like 50% of the time, and that is why I kept working on getting astrometry.net to work offline. Sometimes ASTAP simply times out while solving without logging any specific reason.


With Sextractor & astrometry.net you have a powerful solver.

Out of curiosity and product improvement I like to investigate why ASTAP is not working for you. What binning did you set in Solver settings? See below:


1) For ASTAP you shouldn't bin too much. The resulting image after binning should be 1280x960 pixels or more. So the binning typically should be set at 2x2 in above menu and in the ASTAP menu at 0=auto.
2) An other reason for unreliable solving could be a FOV error. Your screenshots indicated 25.5' x 20.4'. If you load an image in the GUI of ASTAP, is the same FOV indicated in the statusbar of ASTAP?
3) If the exposure time for the image to solve is long it could be that the G18 star database up to magnitude 18 is required rather then the G17. (remove the G17 to force use of the G18)

These causes of poor solving performance can be checked by inspecting the FITS image in /tmp created by EKOS.

In the latest versions of ASTAP some improvements have been added for more reliable solving. Blind solving speed has been increased with about 25% in the latest version 0.9.382.

Han
author of ASTAP

Read More...

Once you have the G18 up to magnitude 18 there is no need for the G17. The G18 will work also for wide field. Inside ASTAP you can configure to use the G18 but the G17 will just take disk space, so best is to uninstall/remove.

I recently added Debian installer for G18. The .290 files from the zip file have to be extracted and copied or moved to /opt/astap

Read More...

Since your using INDI, so Linux I was incorrect about the Astrometry.net version. In Linux you can have the latest Astrometry.net version. But using the correct settings can help like binning or limit the number of objects. Still the online star database of Astrometry.net is better

If your using ASTAP with this small field it is better to use the G18 catalog and remove the G17 catalog. But for these difficult images, Astrometry.net could be better. For ASTAP you can filter out hot pixels with a minimum size or by calibration with a dark but first try it with Astrometry.net since it will be the best change of success.

Han

Read More...

The online solver is better then the older local version (v0.38). The online version has also a better (copyrighted) star database .

The image is difficult to solve. Many hot pixels and poor stars due to long focal length a poor seeing. Maybe also focus. It is possible that the image can only be solved by the online solver. An other reason could be missing index files for the small FOV.


The image is highly oversampled. Both for the image quality and solving a focal reducer could help. An other solution could be to use the guide scope for solving if any.

Han

Read More...