Re: RA reading keeps changing during sidereal tracking

Howard Dutton

OnStep defaults to Topocentric coordinates, which incorporate the effects of refraction.  Tracking does not, by default, incorporate refraction (for good reasons.)

That confuses users, you are not the first.

I wonder if the decision to use Topocentric is even valid anymore, the main reason CdC not handling ASCOM coordinates properly, has probably been fixed by now.  Perhaps in OnStepX I will switch back to default Observed Place.

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