Kowa BD II XD 10x42 vs Kowa Genesis 33 8x33
Quick take: The Kowa BD II XD 10x42 costs $770 less; the Kowa BD II XD 10x42 reaches farther (10x vs 8x); the Kowa Genesis 33 8x33 has a wider field of view (420 vs 315 ft @ 1000 yds).
Field of view, to scale
you2505007501000 yds
Distance200 yds
Kowa BD II XD 10x426.0°
63 ft wide at 200 yds ≈ 1.6 school buses
Kowa Genesis 33 8x338.0°
84 ft wide at 200 yds ≈ 2.1 school buses
Top-down view · drawn to true scale — no exaggeration
| Spec | Kowa BD II XD 10x42 | Kowa Genesis 33 8x33 |
|---|---|---|
| Approx. price | ~$380 | ~$1,150 |
| Rating | — | — |
| Use case | Birding | Birding |
| Magnification | 10x | 8x |
| Objective | 42mm | 33mm |
| Exit pupil | 4.2mm | 4.1mm |
| Field of view | 315 ft @ 1000 yds | 420 ft @ 1000 yds |
| Eye relief | 15mm | 15mm |
| Close focus | 5.9 ft | 5 ft |
| Prism | Roof | Roof |
| Glass | ED | FL |
| Coating | Fully Multi-Coated | Fully Multi-Coated |
| Weight | 24 oz | 20.8 oz |
| Dimensions | 5.6 x 5.0 in | 5.1 x 4.7 in |
| Warranty | Limited Lifetime | Limited Lifetime |
Feature comparison
Kowa BD II XD 10x42
- ✓ED Glass
- ✓Phase-Corrected
- ✓Dielectric Coating
- ✓Waterproof
- ✓Fogproof
- ✗Image Stabilized
- ✓Tripod Adaptable
- ✗Magnesium Body
- ✓Locking Diopter
Kowa Genesis 33 8x33
- ✓ED Glass
- ✓Phase-Corrected
- ✓Dielectric Coating
- ✓Waterproof
- ✓Fogproof
- ✗Image Stabilized
- ✗Tripod Adaptable
- ✓Magnesium Body
- ✓Locking Diopter
What birders say
Kowa BD II XD 10x42
- ✓Class-leading field of view for a 10x42 roof prism - the wide-angle design is the whole reason this model gets recommended, letting birders follow small, fast birds with ease
- ✓XD lenses with fluorite-rich ED glass deliver strong chromatic aberration control for a sub-$400 binocular
- ✓Outstanding 5.9 ft close focus makes it a legitimate dual-purpose bird-and-butterfly instrument
- ✓Bright, sharp central image - owners report identifying ducks and loons at distance and following birds in dark forest understory
- ✓Light for a full-size 10x42 at 24 oz with a well-made magnesium-reinforced body
- ✓Enough eye relief for most eyeglass wearers, per birder owner reports
- ✓Exceptional value: reviewers consistently frame it as delivering mid-tier performance at an entry-plus price, and one owner repurchased the identical model without hesitation
- ✓Kowa's warranty and repair service earn specific praise from owners who have used it
- ✗Edge-of-field distortion and softness are the explicit tradeoff for the huge field of view - critics note the wide view comes with visible compromises
- ✗Bench testing by a forum member flagged roof-edge diffraction artifacts and design compromises from the short focal length
- ✗Some owners have had to send units in for focus-slop repairs, pointing to inconsistent quality control
- ✗One hunting-forum user found the focus wheel uncomfortable and imprecise - handling opinions are split
- ✗Some chromatic aberration remains visible despite the XD glass, especially off-center
- ✗Made in China rather than in Kowa's Japanese factory, which surprises buyers who associate the brand with Japanese production
- ✗Not in the same brightness league as premium 10x42s in twilight conditions
- ✗Durability reports are mixed enough that some forum members recommend buying from dealers with easy return policies
Kowa Genesis 33 8x33
- ✓Prominar XD fluorite-class glass with essentially no visible color fringing — one owner review flatly reported 'zero discernible chromatic aberration'
- ✓Forum reviewers judge it 'optically equal' to the Leica Ultravid HD 8x32 — a binocular that costs nearly twice as much
- ✓Wide 420 ft field of view with a crisp, bright image boosted by phase coating and a dielectric C3 prism coating
- ✓Outstanding 5 ft close focus with minimal visual field collapse — a genuine butterfly and dragonfly instrument
- ✓Light and compact: 22.2 oz on a magnesium frame, about 5.25 inches long — easy all-day carry
- ✓Thoughtful ergonomics with broad, shallow thumb divots on the underside — reviewers note it especially suits smaller hands
- ✓Slow, precise 1.6-turn focuser rewards deliberate focusing and holds position securely
- ✓Repeatedly called 'the best kept secret in premium midsize binoculars' on birding forums — alpha-level glass at roughly half alpha price
- ✗Eye relief is only 15mm and multiple reviewers flag it as 'a bit on the short side' — eyeglass wearers can struggle to see the full field
- ✗The focus mechanism is stiff and slower than average at 1.6 turns close-to-infinity — quick birding refocusing takes more effort
- ✗Eyecups offer just two intermediate stops, limiting fine adjustment for non-glasses users
- ✗The rainguard is hard plastic rather than flexible rubber — a cheap-feeling accessory on a $1,100 binocular
- ✗The included case lacks a shoulder strap or belt loop attachment
- ✗Kowa's small dealer footprint and marketing mean low brand recognition and thinner resale demand than Zeiss, Leica, or Swarovski
- ✗The focus stiffness reviewers hope will 'loosen with extended use' is a break-in gamble at this price
- ✗At $1,100+ it faces its own stablemate problem — the Kowa BD II XD line delivers much of the experience for a third of the money