Carl Zeiss Contax 500mm f/4.5 Mirotar T* mirror lens

see also:

• super telephoto mirror lenses

• this super telephoto lens is a catadioptric mirror lens, and as with all such mirror lenses, share the following characteristics:
  • manual focus
  • fixed aperture (in this case f/4.5)
  • 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

• 500mm focal length and field of view (5°)
• fixed f/4.5 aperture
• 5 groups, 5 elements (including mirror), T* multicoating
• closest focus 3.5m
• 151mm slip on cap
• 3 position turret for ND filters
• rear drop in filters
• 151mm diameter, 225mm long and 4.5g

• http://www.contaxcameras.co.uk/slr/slrmanlenses/mirotar50045.html