William Optics SWAN is a well-designed, wide-angle eyepiece with large lenses for small amounts of money. Own field of view of the eyepiece (AFOV) equal to 72 °. The optics are fully covered with good anti-reflective layers. • own field of view equal to 72 ° • all glass - air boundaries covered with very good layers • extraordinary correction of chromatic aberration • sharpness and good contrast • parfocal with glasses from the series • the whole interior of the eyepiece well blackened (baffle, the edges of the lens) • Extremely large offset of the base tube equal to 28 mm • anodized black body, mechanically resistant • equipped with a 2 "filter thread • model: SWAN 40 • focal length: 40 mm • optical construction: 5 elements in 3 groups • own field of view (AFOV): 72 ° • eye relief : 28 mm • Luminaire diameter: 2 inches • layers: FMC • parfocality: yes • weight: 570 g 2 years


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