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


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