Stargazing Telescope Guiding Techniques: Improving Exposure Times through Auto Guiding

[sophiecentaur]

@Drakkith : Unknown unknowns?
To be fair, I didn't explain it as well as Gaston did and he actually showed that it works. You would have needed to believe an old BS'er to take what I said as being gospel.
Your problem now is that you WANT ONE!

There is an old joke in signal processing community, "without any noise you do not need any signal".

Mr Shannon got it right all those years ago and he had virtually no hardware to test the idea.

 

[russ_watters]

I'm locking this thread for being overly speculative and will likely (when I get a more time later) split it between two threads:
1. A thread on real Telescope Autoguiding Techniques to help people improve their autoguiding (what the title of this thread implies it should be about).
2. A thread on this new full-frame guiding idea proposed by @Gaston Baudat

Please note:
The provided materials on the full frame guiding method are dense, yet and a bit thin in details (explicitly saying they won't go into the details). However, it appears to say that the secret sauce is in the noise filtration technique, not in the multi-star guiding technique. The objections raised to the idea of multi-star guiding previously and the circularity of the argument still appear to apply (if you can't track one star then you can't track more than one star, but what if you can track more than one star...?, you can't track one star, so you can't track more than one star). Anyway, frankly, the quality of the noise filtering appears to me to be too good to be true.

Multi-star guiding exists and has two advantages that don't apply to most people (which is why it isn't used much) or apply to the previous discussion:
1. If seeing is really bad and you have several guide star candidates of similar SNR you could jump back and forth between them as the SNR goes from "not enough" to "enough" for individual stars in successive frames. This would be a rare situation and when seeing is that bad you probably don't want to be imaging anyway.
2. It can allow you to correct for field rotation during imaging -- in only some cases and only if you have special equipment to rotate the camera while imaging. Field rotation is generally corrected after imaging, using a similar technique in software. It requires combining shorter exposure images.