Rene,

GPG should improve your PE for sure. It takes a few mount periods to reach its full potential (as it has to sample your periodic error before it can correct it).
More or less, all you need to do is check the box to turn it on (and it's probably best to also set the period--see below).

- In the guider tab, click Options in the lower right corner.
- Click on "GPG RA Guider" on the left to get to the GPG section
- Check the enable GPG checkbox.

The only control you should consider changing is to set "Major Period" with the period of your mount and, if you know that, disable the "estimate period" checkbox.
You would only do that if you knew your mount's period. Many are given on this PHD2 wiki page: github.com/OpenPHDGuiding/phd2/wiki/Mount-Worm-Period-Info
If you don't know it, you can let the GPG system estimate it, and then if you were happy with the guiding, e.g. after an hour, re-open that menu, look at the value it's estimated,
and freeze that value in there by unchecking estimate period. Of course, I suppose you could let it continue to always estimate, but it will get to its best sooner
if you give it the right period to start with.

Once it's setup, then you're good, and run guiding as you would.
The RA guiding is then controlled by this GPG algorithm.

Let me know if you have any further questions, and/or let us know how it goes.
Hy

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