User Tools

Site Tools


photo:pentaxsmc2000mmf13.5

Table of Contents

Pentax SMC 2000mm f/13.5 mirror lens

introduction

  • this super telephoto lens introduced in ? is a catadioptric mirror lens, and as with all such mirror lenses, share the following characteristics:
    • manual focus
    • fixed aperture (in this case f/13.5)
    • virtual elimination of chromatic aberration as uses mirror rather than lenses
      • also means focus position for infrared photography is the same as for light photography
    • central mirror:
      • allows much more compact lens length as the optic path is reflected internally twice
      • by necessity, blocks some of the light and thus causes:
        • decrease in image contrast
        • characteristic “doughnut” shaped bokeh imagery in out of focus areas

specs

  • 2000mm focal length and field of view (1.25°) at infinity focus
  • fixed f/13.5 aperture
  • 6 lens elements, 4 groups
  • closest focus 20m (0.12x macro)
  • 52mm rear filter thread
  • built-in ND filters (-1 stop, -1.5 stop, -2 stops)
  • built-in skylight, yellow and red filters
  • Pentax K lens mount
  • 180mm diameter, 520mm long and 8kg
  • NB. the later Pentax-M version is virtually identical

reviews

photo/pentaxsmc2000mmf13.5.txt · Last modified: 2014/05/18 09:23 by gary1