Silva Pocket 7X Monocular
The Silva Pocket Scope monocular can be brought anywhere and anytime, taking very little space in the pocket or bag. BAK-4 optics made of superior optical glass that produces clearer images, and a quick focus function provide great optical performance and ease of use. A lightweight, compact monocular is an underestimated aid.
The Silva Pocket 7 power magnification Monoculars are not just for watching birds and other animals. From a kayak you have to find the right routes among outcrops and islands so that you don’t head in the wrong direction. They can help with route choices through valleys or over hills when out walking. Silva’s monoculars and binoculars are compact and sturdy enough for the great outdoors – natural travel companions that can be packed in your rucksack with the same straightforwardness as your compass.
- GREAT OPTICAL PERFORMANCE: Bak-4 optics high quality glass
- CLOSE FOCUS: Perfect detail on close-up objects
- PERFECT FOR DAYLIGHT CONDITIONS: 018 mm lens
- MAGNIFICATION: 7 Power
- Size: One Size
- Field of View: 480 feet [147m]
- Magnification: 7X Power
- Objective Lens Diameter: 18mm lens
- Size: 3" x 1.15" [76 x 29mm]
- Weight: 1.62oz [46g]
- Prism Type: BK-4
- Water Resistance: IPX6 - Splash Proof
- Nitrogen gas Filled: No
- Usages: Hiking, Camping, Birdwatching, Outdoor Activities
TECHNOLOGIES: BAK-4 vs BAK-7
BAK-4 is a high density glass of better optical quality than BK-7. With BAK-4, if you hold binoculars away from your eyes and up to the light you can see the circular exit pupils in the eyepieces. The less expensive BK-7 prisms have squared-off, non-circular exit pupils.
The prism is alike: Bak4 prism costs more than Bk7 prism - Bk7 prism is fine to most of the users, but, to some "picky" users, Bak4 prism is a must. The difference is the quality of glass and anti-reflective coatings.
The design of the prisms can affect the quality of the exit pupil. The BK7 prism typically found in lower priced binoculars produces an exit pupil with shaded (blurred) edges, whereas the BAK4 prism has a perfectly round exit pupil. Whilst the BK7 prism design would look no different to the BAK4 in daylight, as the light levels drop, and the eye pupil expands you start to observe the effects of the shaded regions as the image quality drops and becomes prone to chromatic aberration around the periphery of the image.
See the illustrations bellow