Celestial Navigation · Time — Watch Error and Time of Sight
The GMT of a sight is found from the watch reading by applying the:
- AWatch error (and any zone difference) to convert watch time to GMT✓ Correct
- BEquation of time only
- CDip correction
- DAssumed longitude
Explanation
The observer notes the comparing watch time and applies the watch error (and the relationship of the watch to GMT) to get the exact GMT of the observation, which is then used to enter the Almanac for the body's GHA and declination.
Authority: Bowditch (Pub. No. 9), Time
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