Zoom binoculars area of use watersports magnification 10 x lens diameter 25 mm zoom factor 3 times prism system porro exit pupil diameter 25 mm min focus distance 5 m angle of view 19 field of view in 1000 m 33 m twilight factor 158 relative brightness 6 25 focussing system central focus viewing straight binocular coating multi coated weight 315 g eye relief 58 special features for spectacle wearers rubber armouring