Article: 75mm lens at f/8.7

Discussion in 'Open Discussion' started by phigmov, Jul 16, 2015.

  1. phigmov

    phigmov Mu-43 Hall of Famer Subscribing Member

    Apr 4, 2010
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  2. Machi

    Machi Mu-43 Veteran

    May 23, 2015
    Ralph is fascinating instrument but numbers are wrong.
    It's 657.5 mm f/8.7 camera. 75 mm is aperture diameter.
    Most interesting feature of the Ralph instrument is that "lens" (unobscurred, off-axis, three-mirror anastigmat design) feeds multiple
    CCDs for panchromatic and color photography and even near-infrared spectrometer.
    Second camera, LORRI, is 2630mm f/12.6 reflective telescope (Ritchey-Chrétien design).