Full Resynthesis

The Full Resynthesis tool aims to help to fix badly distorted stars using Siril's star fitting functions. It can be helpful for rescuing images that suffer from bad coma or other distortions. If Siril can detect the stars it can fix them.

The tool is located in the Image Processing menu, in the Star Processing sub-menu.

The output of the tool is a synthetic star mask. In order to make use of this, it must be recombined with a starless version of the original image. This can be prepared using the starnet command or Starnet GUI tool, or using third party star removal software.

This tool has no options, you simply click on the menu item to use it, or use the command synthstar.

If no stars have been detected in the image, the tool will automatically detect stars using the current star modelling parameters accessible via the Dynamic PSF tool or using the setfindstar command.

If stars have been modelled using the Dynamic PSF tool or the findstar command, the detected stars will be resynthesized using their individual modelled luminosity profiles. A shortcut to the Dynamic PSF tool is provided by means of the configuration button in the GUI menu next to the Full Resynthesis tool.

It is recommended to carry out star detection manually first, as it allows verification of the results: if any galaxies have been incorrectly detected as stars, they can be removed from the list of stars before running resynthesis.

Once the synthetic star mask has been created it can be combined with the starless image using the Star Recombination tool.

Commands

Siril command line

synthstar

Fixes imperfect stars from the loaded image. No matter how much coma, tracking drift or other distortion your stars have, if Siril's star finder routine can detect it, synthstar will fix it. To use intensive care, you may wish to manually detect all the stars you wish to fix. This can be done using the findstar console command or the Dynamic PSF dialog. If you have not run star detection, it will be run automatically with default settings.

For best results synthstar should be run before stretching.

The output of synthstar is a fully corrected synthetic star mask comprising perfectly round star PSFs (Moffat or Gaussian profiles depending on star saturation) computed to match the intensity, FWHM, hue and saturation measured for each star detected in the input image. This can then be recombined with the starless image to produce an image with perfect stars.

No parameters are required for this command

Links: psf