Go to Focus/Go to Target

Sequence Generator
1

Dear all,

Last night I was trying to understand and practice how the “Focus Target” and “Focus Position” work. I guess I figured it out. However, when I click “Go to focus” the focus star is not in the center of focus anymore, although I did a platesolve in the star before hand and it was centered. The same happened when I issued the “Go to focus”.

I wonder what I am doing wrong?

Thanks in advance, Fernando

2

@Fernando I can’t be certain. You would need to describe your workflow in more detail. I am assuming you properly set the focus position first?

Also, as a note… this functionality is not typically used anymore… even if you are focusing manually. This feature predates addition of auto focus in SGPro. I highly recommend exploring “on-target” focus options before you invest time in moving back and forth between targets. For manual, “on target” focus, start, frame and focus and ensure that the “Image History” option is on. See here:

http://www.mainsequencesoftware.com/Content/SGPHelp/ImageHistory1.html

3

Thanks Ken. I got a Pegasus autofocuser for my SW Esprit 120ED. Got to get some time to install it… Kind of lazy…:))))

Regards, Fernando

4

My question is slightly related: If I’m doing a deep sky object that has few stars for the autofocus routine, is there a mechanism for an automated slew to a nearby star, focus, then return to target?

Thanks!

5

@Ken - I started to wonder if the focus target might be useful again. Some targets are challenging for AF, like globular clusters. If a focus target with the cluster out of sight could be set up and the auto slew/center controls activated, I could see the following might avoid trying to re-write an AF routine to cope with extreme targets:

  • AFtrigger - if focus target set, slew to focus target
  • perform AF
  • slew and center back to imaging target
  • continue guiding and exposure sequence

What do you think - all the elements are already there…?

6

@buzz. Yes, we have this in our backlog of things to do and it would alleviate pressure on AF to be successful all the time even in the face of star poor regions and data. Injecting this functionality into automation is likely a worthwhile, but time consuming exercise. We’ll see what we can do.