Two eyes, a wide field, and no setup at all · review
A long-running 10x50 porro binocular from Bushnell's Falcon line, with BK-7 prisms, fully coated optics and a central InstaFocus lever, and no waterproofing claimed.
Ten times and fifty millimeters is the classic astronomy binocular. The 5 mm exit pupil matches an eye adapted to the dark, and the porro prism layout gives a wide, slightly three-dimensional view that cheaper roof-prism pairs do not.
Bushnell says fully coated, and the description names BK-7 porro prisms. Fully coated means one antireflection layer on each surface; better pairs say fully multi-coated. BK-7 can clip the edge of the light cone slightly, where BaK-4 gives a round exit pupil.
Neither is a fault at this price. Both cost a little contrast on faint objects.
The Amazon.com listing has a bullet that reads “12x magnification, 50-millimeter objective lens”. The model name, the title and Bushnell’s own description all say 10x50. Trust the model name.
No waterproofing, no gas filling, no field of view figure, no eye relief. Amazon’s item data gives a weight of 830 g (29.3 oz). Keep it out of the rain and let it warm up indoors in a case so the lenses do not fog.
A 10x50 shows the Moon’s terminator, Jupiter’s moons, the Pleiades, the Andromeda Galaxy and the summer Milky Way whatever its coating grade. The InstaFocus lever makes the change from a nearby treeline to the stars quick. As a first pair, or a spare kept in the car, it does the job.
On November 7, 2026, Amazon.com sold it directly at $40.78.
Figures as Keepa reported them on the day this page was last updated. Stock and pricing shift without warning.
Prices quoted in this text were read on November 7, 2026. The live price is at the top of the page.
Same aisle, closest price — what the same spend else shows.
| Aperture | 50 mm (1.97 in) objectives |
|---|---|
| Magnification | 10x in the title and the description · one bullet of the same listing says 12x, which contradicts the model name |
| Exit pupil | 5 mm (0.20 in) at 10x, the quotient of the published figures |
| True field of view | Not published by the maker · sold as wide-angle |
| Prism type and coatings | BK-7 porro prisms · fully coated optics (not multi-coated) · no waterproofing or gas filling claimed |
| Eye relief | Not published by the maker. |
| Close focus | Not published by the maker. |
| Weight | Not published in the listing text · Amazon's item data gives 830 g (29.3 oz) |
| Tripod mounting | Not published by the maker. |
| Supplied accessories | Not published by the maker. |
| Amazon reference | B000051ZOA |
| EAN | 0029757334503 |
10x. The model name, the title and the manufacturer's description all say 10x50; one bullet in the same Amazon listing says 12x, and that bullet is the error.
Fully coated means every air-to-glass surface has at least one antireflection layer; multi-coated means several layers. Each extra layer cuts reflection further, and on faint objects that is visible as a slightly brighter, more contrasty view.
In a porro prism, BaK-4 gives a perfectly round exit pupil where BK-7 can show slightly squared-off edges, which loses a little light at the margins. It is a real difference and a small one; at this price it is the expected glass.
7.2/ 10
An honest, unsealed, lightly coated 10x50 whose porro prisms do more for the view than its price suggests.
This model is listed on Amazon.com, at ≈ $41 at the last reading. Listed is not the same as in stock: availability changes daily, and the buy box shows the live price.
Details checked on November 7, 2026.
A first, inexpensive pair kept in the car for whatever the sky or the day offers
Amazon reports what buyers took in the month before this page was last checked: at least 400.
The figure is a floor, rounded by Amazon, and read through Keepa — it says what buyers picked, not what a maker claims.
Specifications: the manufacturer sheet for telescopes and observing optics and the matching Amazon product page. Prices and availability: Keepa. Every figure on this page names its source.
10x · 50 mm (1.97 in) · porro prisms · multilayer-coated · long eye relief
Nikon's Action 10x50: a rubber-armored porro binocular with multilayer-coated lenses, turn-and-slide eyecups, long eye relief for glasses and a tripod-ready body.
Best for: Sweeping the Milky Way and open clusters, on a tripod or from a reclining chair
≈ $130
10x · 50 mm (1.97 in) · 282 ft field at 1000 yd · BaK-4, silvered prisms · 26.1 oz (740 g)
A waterproof, nitrogen-filled 10x50 with BaK-4 prisms carrying an extra silver coating, published with its field of view, close focus, dimensions and weight.
Best for: The observer who wants to compare figures rather than adjectives before buying
≈ $226
10x · 50 mm (1.97 in) · BaK-4 prisms · waterproof, gas-filled · 758 g (26.7 oz)
A waterproof, gas-filled 10x50 porro binocular with BaK-4 prisms, full multi-coating, a UR prism coating, twist-up eyecups and a metal center focus, published with its weight and size.
Best for: Dusk and night-sky use in damp or cold weather that would fog an unsealed pair
≈ $166
