TeleVue 1.25" Enhanced Aluminum 96% Reflectivity Mirror Diagonal

This 90° 1.25" mirror-type star diagonal uses enhanced aluminum mirror coatings for a full 95% reflectivity. The mirror is overcoated with quartz for long life. The mirror housing and 1.25" barrels are precision-machined from a single block of solid aluminum, rather than being simply a pair of less-rigid tubes screwed into a flimsy plastic mirror housing or sheet metal stamping, as with lesser imported diagonals. A solid metal backplate over 4/10ths of an inch thick holds the mirror securely in the correct optical alignment. Both focuser and eyepiece barrels are antireflection threaded internally for higher contrast. The 1.25" barrel that fits into the focuser or visual back is also threaded to accept standard 1.25" filters.

The 1.25" eyepiece barrel uses a non-marring soft brass compression ring to hold eyepieces in place, rather than a thumbscrew that contacts the eyepiece barrel directly. A groove cut into the outside of the barrel acts as a safety stop to keep the diagonal from falling should the scope's visual back or eyepiece holder thumbscrew loosen slightly from cold or use.

This premium 1.25" diagonal is a worthy and visible upgrade for virtually any Schmidt-Cassegrain, Maksutov-Cassegrain, or refractor that uses a 1.25" prism-type star diagonal.