I have recently moved from a refractor back to using a C9.25 SCT for imaging.
Whenever the focuser movement is inward it always go directly to the position specified.
However, when the focuser movement is outward it always overshoots and then comes back in to get to the final position.
I may be wrong but I assume that this is deliberate because of the way that SCT's move the mirror for focussing.
I do not need to concern myself with this as I have a separate focuser attached to the rear cell.
I want to stop this behaviour.
Are my assumptions above correct and how do I stop this, other than defining the telescope as a refractor?
Paul

Hi Paul,

Sounds like you have AF Overscan set. Here, in this example its set to 250...


This means outward movements overshoot by 250 ticks then move back in by 250 ticks. Set it to zero to disable this effect.

John,

Prior to your response I decided to see whether the AF Overscan had any effect and had it set it to zero but was waiting for a clear night.

As you suggested that solved the problem.

I assume that when I created a new profile it automatically set it based on the telescope type.

Paul

The defaults are Driver Backlash = 0, AF Overscan = 100.

The thought was that most people have some form of backlash that needs to be neutralised. Not all device drivers support backlash so setting those defaults give a starting point. Everybody needs to adjust for their own setups though.

Glad you issue is resolved.