This remarkable feature is responsible for never-seen-before functionality that allows you to, for example, apply correct deconvolution to heavily processed data. The deconvolution module "simply" travels back in time to a point where the data was still linear (deconvolution can only correctly be applied to linear data!). Once travelled back in time, deconvolution is applied and then Tracking forward-propagates the changes. The result is exactly what your processed data would have looked like with if you had applied deconvolution earlier and then processed it further.
Sequence doesn't matter any more, allowing you to process and evaluate your image as you see fit. But wait, there's more!
Time travelling like this is very useful and amazing in its own right, but there is another major, major difference in StarTools' deconvolution module;
Because you initiated deconvolution at a later stage than normally can be the case, the deconvolution module can take into account how you further processed the image after it normally should have been invoked. The deconvolution module now has knowledge about a future it normally is not privy to in any other software. Specifically, that knowledge of the future, tells it exactly how you stretched and modified every pixel - including its noise component - after the time its job should have been done.
You know what really loves per-pixel noise component statistics like these? Deconvolution regularization algorithms! A regularization algorithm suppresses the creation of artefacts caused by the deconvolution of - you guessed it - noise grain. Now that the deconvolution algorithm knows how noise grain will propagate in the "future", it can take that into account when applying deconvolution at the time when your data is still linear, thereby avoiding a grainy "future", while allowing you to gain more detail. It is like going back in time and telling yourself the lottery numbers to today's draw.
What does this look like in practice? It looks like a deconvolution routine that just "magically" brings into focus what it can. No sub-optimal local supports needed, no subjective luminance masks needed, no selective blending needed. There is no exaggerated noise grain, just enhanced detail; objectively better results, in less time.
And all this is just what Tracking does for the deconvolution module. There are many more modules that rely on Tracking in a similar manner, achieving objectively better results than any other software, simply by being smarter with your hard-won signal. This is what StarTools is all about.
Deconvolution of planetary, solar and lunar images can be achieved as well by switching 'Image Type' to 'Lunar/Planetary'.
The 'Regularization' parameter controls the balance between newly recovered detail and noise grain propagation.
Understanding the former two important points will make clear why the various parameters exist in this module.
The way a point light is blurred like this, is also called a Point Spread Function (PSF).
Pixels that are not suitable are areas that contain aberrant data, no data, or data that is non-linear.
You can convert everything you see to a format you find convenient. Give it a try!