SGP auto focusing

When I use SGP’s auto focus I never seem to get below 1.9 - 1.8 HFR, but a friend of mine gets down to about 0.5.
Also her V curve is far better than mine.

I was wondering what effects the lowest HFR one can expect?
Clearly I assume seeing conditions has an effect (but my results were consistent over several nights).
What else effects the result?
Is it dependent upon camera pixel size?
Is it dependent upon scope aperture or focal length?
Anything else?

Mount: AZ EQ6-GT on a fixed pier.
Scope: Vixen AX103S.
Camera: Canon 5D Mk2.
Focuser: Lakeside Motorised Focuser.

The HFR numbers in SGP are in units of camera pixels so you really cannot compare them. The numbers will also change if you change binning.

That raises an idea for a feature request… SGP knows the image scale so it would be great if it could display HFR numbers in units of arc-seconds!


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