Product Details

Davis Mark 15 Master Sextant W/Guide/ Case/ Precise Marine Navigation Instrument. The object shown is a Davis Mark 15 Master Sextant, a popular and precise marine navigation instrument manufactured by Davis Instruments. Material & Build: Made from lightweight, heavy-duty, non-deformable black plastic designed to be corrosion- resistant and shockproof. Optical Features: Equipped with a 3x27 mm star telescope and seven large sunshades for sighting celestial bodies relative to the horizon. Precision: Features an easy-to-read micrometer drum and vernier scale capable of reading down to 0.2 minutes of arc. Here are the essential operating instructions for taking a celestial sight using the Davis Mark 15 Master Sextant. 1. Check for Index Error Before taking any measurement, you must account for instrument error: Set the index arm and the micrometer drum precisely to 0° 00.0'. Look through the telescope at a sharp, flat horizon.If the reflected horizon and the direct horizon do not form a s