How to use the Focus Module to focus on a galaxy

Hi,

what I did up to now is to focus manually or with auto focus on a star, which works fine!
But which settings to focus on a great object like M31 galaxy?

Sub frame or full frame?
Focus the center of the galaxy or the stars at the edge of the galaxy?

Regards,
Armin

What I do is slew to a good nearby star, then use that to focus, then back to the main target (using the alignment module).

I use my bahtinov mask, since my internal focuser is not currently working for me (the donut issue).

To help avoid confusing the focusing star detection with the faint fuzzies, you can try full frame focusing with the central area excluded

@ Megiddo: Which donut issue do you mean? Because I also see donuts after auto focus!

@ Ihoujin: What are the settings for " full frame focusing with the central area excluded"? Maybe you could provide a screenshot?

arminpro wrote: @ Megiddo: Which donut issue do you mean? Because I also see donuts after auto focus!

You can see it in this thread: https://indilib.org/forum/focusers-filter-wheels/5447-odd-my-focuser-did-the-opposite.html

The focuser module starts by moving in/out and if it does it too much and creates the donut, it gets lost. I've tried pretty small step values, which makes me think I need to try even smaller steps. Tonight I'll try 5 or something tiny. (assuming clear skies)

I can't offer screenshots at this time, but you will find among the check boxes in the focus module one called full frame. Then there are two fields to enter % of inner and outer fields to exclude. They are used to avoid confusion in the center and stars with aberration in the corners.

Thank you Ihoujin!