Photo Credit: Davis Instruments
Featuring a precision-machined, slow travel gear and worm mechanism, the dependable Mark 15 has a 7″ frame radius graduated from 120° to -5°. It also includes seven large sunshades, a star scope with anti-reflective glass lenses and a separate hooded sight tube for glare-free sun shots. Designed for the harsh marine environment, the durable sextant has a contoured handle and angled back for a steady grip and added control.
The Deluxe Mark 25 Sextant adds a Beam Converger, LED light and advanced mineral coating. Replacing the traditional, half-silvered mirror, the Beam Converger provides a single, full-field view for reliable sights, even under the most difficult conditions. The highly-efficient, long-life LED illuminates the arc and drum, while a special, mineral coating enables users to see the horizon in one color and a star or the sun in another. This helps to pick up faint objects such as low-light stars as well.
Source: Davis Instruments