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Date/Time Mismatch Warnings

Date/Time Mismatch Warnings allows you to display (checked) or suppress (unchecked) warning messages displayed by Deep-Sky Planner when it connects to a telescope or DSC that has a different date/time (UT) from your PC system date/time (UT). 'Mismatch' in this sense means that the date/times differ by more than 1 day. This switch is disabled if telescope control is not set up.

A difference in times affects the accuracy of the Slew To and Sync To features, and has greatest impact when slewing to sun, moon, planets, comets and asteroids. In addition, the ephemeris for the aforementioned solar system objects should be calculated for the current PC system time (Now) before requesting Slew To or Sync To operations.

What about?

I slewed my telescope to an object. Why does the telescope slew to an equatorial position slightly different from a cataloged object's reported position? Cataloged objects' positions are referred to epoch J2000, but an object's position in the sky changes slightly over time due to precession. Deep-Sky Planner precesses a cataloged object's position to the epoch of the report's ephemeris date before sending the Slew To command to the telescope.

I slewed my telescope to a solar system object. Why does the telescope slew to an equatorial position slightly different from its reported position? Solar system objects' positions change constantly over time. Some comets and Near-Earth Objects (asteroids) may move more than a degree per hour; other objects move very slowly. Deep-Sky Planner calculates the position of these objects accurately for the ephemeris date & time selected for the report. To use the Slew To (or Sync To) operations accurately, you should perform the ephemeris calculation for the current date & time before sending the Slew To (or Sync To) command to the telescope.

Additional Information:

▪Setting up your telescope to enable Slew To or Sync To

▪Telescope Control Panel

▪Synchronizing PC system and Telescope time

▪Using a Time Service to set the PC system time accurately