Outdoor binoculars area of use travel nature astronomy outdoor sports magnification 8 x lens diameter 42 mm prism system roof exit pupil diameter 525 mm min focus distance 2 m angle of view 74 field of view in 1000 m 129 m twilight factor 183 relative brightness 27 56 focussing system central focus viewing straight binocular coating fully multi coated weight 670 g outdoor function waterproof