true-to-life image due to high-quality BaK-4 prisms and full multi-coated lensesExcellent value-for-money ratioWeatherproof because watertightNitrogen filling prevents misting of the internal optics if the temperature

geometric light intensity and twilight factor mean? These arithmetical values are calculated from the ratio of magnification and objective lens diameter. Important in practice: an exit pupil between 2 and 3