The 25x81 BT81S-A Astronomical Binocular from Vixen Optics features interchangeable eyepieces that provide exceptional terrestrial or celestial observing. The twin 480mm f/5.9 achromatic refractors have permanently attached 45° diagonals and accept any 1.25" eyepieces. With a broad 56-101mm interpupillary adjustment range this powerful optic will fit nearly any set of eyes, including many children's.
For remarkable depth perception and contrast, there is nothing that beats the ease and comfort of erect-image binocular viewing. Expect high quality observing of terrestrial vistas and celestial views alike which is easily transported to your favorite dark sky location out and beyond. Take a drive to nowhere on a clear, new moon lit night and be awe struck! The Pleiades and the Moon's terminator never looked like this.
This permutation of the BT81S-A arrives with two Vixen 20mm SLV-series eyepieces. The eyepieces are fully multicoated, with long eye relief and twist-up eyecups. A required mount and a tripod or base need to be supplied by the user.
Apparent angle of view: 50°
Accepts any 1.25" eyepieces
Visual back 31.7 mm - friction fit
Built-in carry handle and finder bracket
Mount block dovetail bar for SX/GP tripods
Interpupillary distance adjustment range of 2.2-4.0"
Two fully multicoated Vixen 20mm SLV-series eyepieces with pop-up eyecups
Twin 480 mm f/5.9 achromatic refractor telescopes with 45° incorporated erect image diagonals
In the Box
Vixen Optics 25x81 BT81S-A Astronomical Binocular with 20mm SLV Eyepieces