— Ship's Log
Technical guides, passage stories and certification preparation.
From raw sextant angle to a plotted line of position, one worked solar example at a time.
Step-by-step guide to HO 249 sight reduction tables with a worked solar example. Learn to find Hc, Zn, and plot your line of position.
Read article →Accuracy, speed, weight, and which certifications require which tables.
HO 249 or HO 229? Compare both sight reduction methods — accuracy, speed, and which certifications require which tables.
Read article →GPS can fail. The sky cannot. What experienced ocean sailors know about electronic dependence.
GPS can fail at sea. Here's why experienced offshore sailors still practice celestial navigation — and how to start learning.
Read article →The six competencies, what the examiner tests, and how to prepare without going to sea first.
Preparing for the RYA Yachtmaster Ocean exam? Here's exactly what celestial navigation skills you need and how to practice them.
Read article →The simplest, most reliable celestial observation — and the one every ocean navigator should master first.
The noon sight is the simplest celestial observation. Learn to find your latitude from the Sun's meridian passage — formula, example, and tips.
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