Bushnell Trophy 10×42 Binoculars (334211): Verified Specs and Owner’s Guide Tips

The original post on this site was a product description of the Bushnell Trophy 10×42 binocular (model 334211) in Realtree Xtra camo. This rewrite uses Bushnell’s own owner’s guide for the specifications and setup instructions.

Verified specifications

From Bushnell’s 334211 Trophy owner’s guide:

• Magnification: 10x
• Objective diameter: 42 mm
• Roof prism system with BaK-4 prisms
• Fully multi-coated optics
• Field of view: 305 ft at 1,000 yards (101 m at 1,000 m)
• Exit pupil: 4.2 mm
• Eye relief: 16 mm
• Length: 5.5 in (142 mm); weight: 21.5 oz (611 g)
• Dura-Grip rubber armoured housing, O-ring sealed and nitrogen purged; tested to IPX7 waterproof standards
• Lead- and arsenic-free EF glass
• Twist-up eyecups and flip lens covers
• Tripod adapter socket at the end of the centre hinge
• Included: case, adjustable neck strap, microfibre lens cloth, ocular and objective lens covers

Corrections to the original listing

• A retailer listing for this model quotes 330 ft field of view and 15.2 mm eye relief. Bushnell’s owner’s guide gives 305 ft and 16 mm, so we use the manufacturer’s figures.
• The owner’s guide itself has a typo in its introduction, calling the binocular a “Trophy 10×50”; its cover and specifications table both say 10×42.

What the numbers mean

Every binocular carries two numbers. Astronomy magazine’s binocular guide explains that the first is the magnification and the second is the diameter of each front lens in millimetres, so a 10×42 magnifies 10 times and has 42 mm lenses.

• Exit pupil: aperture divided by magnification. 42 ÷ 10 gives 4.2 mm, as Bushnell lists.
• Why exit pupil matters at night: the same guide says most people under 30 have dark-adapted pupils of about 7 mm, around 6 mm in their 30s, and probably no more than 5 mm from age 40. A bigger exit pupil than your eye can use simply wastes light.
• Field of view: to convert feet at 1,000 yards into degrees, divide by 52.5. 305 ft works out to about 5.8°. Astronomy magazine says most binoculars cover about 6° to 7°, high-power models 3° to 5°, and wide-angle models 8° to 10°.
• Eye relief: Nikon’s guide says eye relief of 15 mm or longer lets most eyeglass wearers see the whole field without removing their glasses. At 16 mm, the Trophy meets that guideline.

Is it good for stargazing?

The 42 mm lenses meet Astronomy magazine’s 40 mm minimum for stargazing, and 10x is the most it recommends for hand-held use. For longer sessions, Bushnell’s guide says you can unscrew the cap on the centre hinge and fit a binocular tripod adapter (a 90° bracket, such as the Bushnell #161002CM) to hold the binocular steady on a standard tripod. A steady view makes it much easier to pick out faint star clusters.

Setting up your binoculars

Bushnell’s Trophy owner’s guide describes the standard set-up that works for most centre-focus binoculars:

• Eyecups: twist them up if you do not wear glasses, so your eyes sit at the right eye relief distance and you see the full field of view.
• Interpupillary distance: point the binoculars at a blank wall or sky and move the two halves closer or farther apart until you see a single circle with no shaded areas.
• Focus the left side: cover the right objective lens, then turn the centre focus knob until a detailed distant object looks sharp through the left side.
• Set the diopter: cover the left lens instead and turn the diopter ring under the right eyepiece, not the centre knob, until the right side is sharp.
• Remember your setting: note the diopter mark so you can reset it if someone else uses your binoculars.

What you can see in the night sky

According to Astronomy magazine, binoculars show the Moon in crisp detail, including shadows moving across lunar features as it waxes and wanes and earthshine on a crescent Moon. They also let you follow the phases of Venus and the motions of Jupiter’s big moons. Beyond the solar system, large star clusters such as the Pleiades in Taurus and the Beehive in Cancer fit nicely in a binocular view, and the Andromeda Galaxy (M31) stands out from a dark site. The magazine says more than 400 deep-sky objects lie within reach of good binoculars from a dark-sky site.

Care and cleaning

The Trophy guide’s cleaning advice applies to any binocular: blow or brush away dust first, then wipe in a circular motion with a microfibre cloth. For a thorough clean, use photographic lens tissue and lens-cleaning fluid, always applied to the cloth and never directly on the lens. Never use household window cleaner or paper towels, which can damage coatings or scratch the glass. Store the binoculars in a cool, dry place.

Safety

Never look at the Sun through binoculars or any optical instrument. Bushnell’s guide warns this may permanently damage your eyes.

Quick summary

• 10×42 roof prism, BaK-4, fully multi-coated.
• 305 ft field, 4.2 mm exit pupil, 16 mm eye relief.
• IPX7 waterproof, nitrogen purged; 21.5 oz.
• Tripod adaptable for steadier night views.

Jargon buster

• Objective lens: the big front lens that collects light.
• Exit pupil: the small bright circle of light you see in each eyepiece when you hold the binoculars away from your eyes.
• Diopter: an adjustment for differences between your two eyes.
• Roof vs Porro prism: roof models have straight barrels; Porro models have the classic zigzag shape.