Hi Patrick,
There are two ways to correct for arbitrary distortions with the StarAlignment tool:
* Distortion models. These are plain text files in standard CSV (Comma-Separated Value) format. They can be generated, for example, with Andrés' ManualImageSolver script.
* Built-in arbitrary distortion correction algorithm.
These features have already been described in a
release Information forum post on the latest version of the StarAlignment tool. Distortion correction has also been
further improved recently.
If you use a distortion model, you can apply the model to the target image(s) only, or also to the reference image. The distortion model is always applied to undistort start coordinates prior to the actual image registration task.
The reference image has no specific requirements. The word "distorted" here refers to some definition of distortion that is beyond StarAlignment's control.
If you want to use a synthetic image as a registration reference, for example one generated with the CatalogStarGenerator script, you can enable SA's distortion correction option. In this way SA will try to "undistort" all target images to match the synthetic reference.
