VIXEN BT81S-A Review

By Haseeb Modi

Vixen BT81S-A Astronomical Binoculars:

Fortunate indeed is an amateur astronomer who gets time to spend under the stars rather than sitting and watching soap operas. Even more fortunate is an amateur astronomer who has a friend who is passionate about astronomy and shares his passion with others.  I am of course referring to the ‘Passionate Astronomer’ who owns a plethora of scopes and equipment and has helped others enjoy this wonderful hobby.

If you recall, I had mentioned in my earlier review about him searching for an instrument which he would cherish. While this instrument may still yet elude him, in the interim period, a Vixen BT81S-A came into his possession.  This Japanese built bino scope is a thing of beauty. One glance and you know you have a winner.

The official specifications:

Magnesium Flouride coated, air spaced doublet design offers to dramatically reduce chromatic aberration and leave you with crisp, clear images. Optical coatings fully multi coated with BAK-4 glass and Porro Prism type. Total weight 9 lbs and..

• Focal Ratio F/5.9
• Aperture : 81mm (3.1")
• Focal length - 480mm
• Resolving Power: 1.43 arc secconds
• Features: Carry Handle, Finder Bracket
• Dimensions: 18.9" x 7.4" x 6"
• Warranty: lifetime.

Note the last part, now that is something.

The package comes in two boxes with the box containing the scope within another. Styrofoam protects all sides from bumps while transporting.

I had the opportunity to check out this binocular scope and take some pictures for the readers to see. The construction is solid as usual and the prisms have that clean, high quality look. The front 81mm objectives are even more brilliant and looking through from a light source, I could see all the way without the slightest aberration, dust speck or anything of the sort.

My friend had a Garrett 5000 series head ready on hand to attach at the bottom plate and a 058B Manfrotto heavy tripod. While I have not yet taken a look through, the owner did and according to him, the downgrade in aperture from 100mm to 81mm has not really impacted the views much. In fact these high quality objectives have provided him with good contrast and pinpoint stars with hardly noticeable chromatic aberrations.

I like the Helical focusers, they look well built and smooth to operate. I would assume from the initial observation made by its owner, the collimation is bang on with no fingernail leakage.  I am still new to binocular scopes so would rely on my buddy to tell me in case to the contrary. To me however, this package reeks of all round quality and a keeper for those already accustomed to bino-viewing.

Haseeb Modi.