Astronomy binoculars hunting binoculars area of use astronomy hunting magnification 20 x lens diameter 70 mm prism system porro suitable for intermediate beginner expert exit pupil diameter 35 mm min focus distance 100 m angle of view 3 field of view in 1000 m 52 m twilight factor 374 focussing system central focus viewing straight binocular coating xlt weight 1 850 g eye relief 20 colour black included in delivery hardcase special f