The BS77iA by Miyauchi

The Miyauchi BS-77iB is a highly portable, very high quality 77mm 45° angle of view semiapochromatic binocular. The compact size and versatility of this binocular sets it apart from binoculars of the same aperture.

The BS-77 employs a four element Petzval semi-apochromatic objective to deliver sharp high contrast images of deep sky objects. Interchangeable oculars set the BS-77 apart from competitive models. The BS-77 Exceed is fully multicoated for increased contrast.

Product # MIA1006

*See Price List for Pricing Information.


Optical System: Semi-Apochromatic/Petzval, 77mm F/5.2, 400mm , 4 element, 3-groups
Body Construction: Duraluminum [Marine grade]
Standard Ocular: 20x -- 2.5°
Dimensions 12" x 7" x 3.5"
Weight 2.5kg [5.5lbs]
Case [optional] Waterproof/Airtight ABS

Oculars for the BS-77

Magnification Eye Relief
Field of View
Apparent Actual
20x 20mm 50° 2.5°
30x 14mm 66° 2.2°