ASCOM focuser temperature compensation

[dts350z]

I noticed BYEOS seems to know when my focuser has a temperature sensor attached. Is there any capability (now or planned) to perform temperature compensation?

 

Between exposures or during exposures (checkbox)?

 

 

[admin]

This is none at the moment, but I would imaging that could become a trigger to initiate the auto-focus when I eventually get back to that feature.

 

Regards,

[dts350z]

Well if you know that your focus changes, say, 25 steps per degree C, then there is no need to "autofocus", you just need to move that 25 steps.

 

I can have the focuser do it itself, but it will happen continuously, during exposures, and while I can arrange for small step changes with small temp changes I don't know if that movement/vibration will show up in the sub frame.

 

By using ASCOM, instead of the focuser internal temp compensation, there is the opportunity to do the compensation between exposures. 

[astroman133]

If you enable temperature comp in the focuser, the changes are so small that they should not be noticeable in your images.

[dts350z]

It's just the vibration that I'm worried about. 

 

Guess I will test with some less the Critical Focus Zone number of steps during exposures and see if I can detect it in the results and/or autoguiding.

[astroman133]

I am considering adding an Innovations Foresight ONAG (on-axis autoguider) to my imaging train.  It uses autoguiding images to do continuous autofocusing.  I asked them about vibration from the focuser while imaging and they said that the focuser movements are so small that the vibration is not noticeable in images.  I am still thinking about it.

[admin]

I am considering adding an Innovations Foresight ONAG (on-axis autoguider) to my imaging train.  It uses autoguiding images to do continuous autofocusing.  I asked them about vibration from the focuser while imaging and they said that the focuser movements are so small that the vibration is not noticeable in images.  I am still thinking about it.

 

I agree with Rick's comment 110%.  Most absolute stepper motor focusers will have several steps per millimeter, sometimes hundreds.  The precision and step size are so minute that any rigid imaging train won't feel the movement at all.  You should probably be most concern about the focuser slipping than focuser vibration.

 

Regards,