autofocusing noobie q

[it344x]

hi everybody,
Been happily using AA since v3, but due to various reasons I have never been able to use an autofocusing unit. This is about to change with a new 'scope in the post :=).

Can anyone point me to a guide or reference on how to use it please, I can't see a clear link on the internet for a complete autofocusing beginner.

How often should I re-focus, can it refocus on the fly, can AA automatically re-focus between exposures?
many thanks
Martin

[Iver]

Hi Martin, if you are using ver.7 latest service pack. The sequencer can be set up to do what you want. Go to the AA help topics and search for Autofocus to learn how to set it up. Then search for sequence that will explain how to incorporate auto focus in a sequence.
Here is a very simple sequence that would take 12 images and refocus every 4 images.

[it344x]

thank you a million Iver!

[Rudi]

I do not usually autofocus for every image, but perhaps every 5 to 6. AutoFocus takes arround 30 seconds on my setup, so doing it every 120 sec image, would "waste" 25% observation time. Doing it every 6'th image, only 4% observation time is lost for focusing. I always let Astroart save focus pos and ambient temperature in the fits file, then I can see how focus develops over time. It looks like there's a very tiny temperature dependency on my current newton and no flex at all.
If I run a L, R, G and B sequence, I would set up the sequencer to do:

Filter: L, N: 6, Exposure: 120, Focuser: 99999
Filter: R, N: 6, Exposure: 120, Focuser: 99999
Filter: G, N: 6, Exposure: 120, Focuser: 99999
Filter: B, N: 6, Exposure: 120, Focuser: 99999
[X] Repeat everything: 6

[it344x]

Does the naming sequence follow what has been set up?
Apologies, I can't find any reference to "sequence" in the help files.

Also, is there a list of autofocusers that AA can communicate with, and does it have to be through ASCOM?

thanks again

[Iver]

Yes that is how it works.
The focuser must be ASCOM.
To activate the Autofocus you need to put 99999 in the focus section.

Here are screen shots of the sections I referred to.