Cassens & Plath Sextant PROFESSIONAL Full-view mirror

Sextant frame and construction

The frame is made from a 5.5 kg brass plate, which is milled to produce a frame weighing approx. 0.6 kg. Once the milling work is complete, the frame is heated in a furnace, straightened, ground and engraved. The individual components are then assembled. Once completed, the sextant consists of over 100 individual parts, most of which are manufactured in-house. All components are assembled and adjusted by hand. Each sextant is tested after manufacture and a quality certificate is issued.

Full-view mirror

The sextant is equipped with a full-view mirror. It is half-silvered and therefore semi-transparent, which means that half of the mirror can be used to look in the direction of the horizon, while the other half reflects the line of sight in the direction of the index.

This has the advantage that the celestial body can be kept in view more easily, even in rough seas, and that the celestial body and the horizon are always in view at the same time. This simplifies measurement. The partially transparent mirror coating slightly reduces the brightness of the horizon image, which can make observations at dusk more difficult.