public void SlewToAltAz(double Azimuth, double Altitude) { if (wisetele.ShuttingDown) { throw new InvalidOperationException("Wise40 is shutting down"); } try { _driverInitiatedSlew = true; wisetele.SlewToAltAz(Azimuth, Altitude); } catch { _driverInitiatedSlew = false; throw; } _driverInitiatedSlew = false; }