National Geographic 8X42 Waterproof Binocular
Waterproof is the specification people look for. Fogproof is the one that actually saves a morning. Water gets in through seals, but fog forms inside the barrels when warm humid air is trapped at assembly and then meets a cold lens at dawn, and once that happens there is nothing to do but wait. Sealing against both is why this pair keeps working when the mist comes off the water.
The 8X42 optical system
Roof prisms made from BAK-4 glass sit behind fully multicoated lenses. BAK-4 is the denser barium crown glass that produces round, evenly lit exit pupils rather than the clipped, squared off ones cheaper prisms give, and multicoating on every air to glass surface cuts the internal reflections that wash out contrast in bright light. Eight times magnification with 42 millimetre objectives is the classic all round pairing.
Field of view and handling
The field of view is 114 metres at 1000 metres, which is generous enough to find a moving bird without hunting for it. Twist up eyecups let spectacle wearers wind them down and everyone else wind them up, and the rubberised shockproof body absorbs the knocks that come with field use. Total weight is 710 grams.
Full features and the complete specification table appear below.
Features
- BAK-4 roof prisms
- Fully multicoated lenses
- Waterproof and fogproof
- Rubberized shockproof body
- Twist-up eyecups allow easy focusing with or without eyeglasses
Specifications
| Magnification |
8 x |
| Objective Diameter |
42 mm |
| Field of View |
114/1000m |
| Optical System |
Roof BAK4 |
| Optical Coating |
Multi-Coated |
| Dimensions |
15x130x55mm |
| Weight |
710g |