This is where the Equation Of Time comes in. The EOT basically tells you the difference between your local solar time and the mean time for your location. If you know for instance that the EOT for a given day is plus five and a half seconds
link you can set your clock which
link must record a day of 24 hours to the correct mean time for your location. Once you have the correct mean or average time for your
link location you can then further adjust the clock to the civil time for your time zone.