User Tools

Site Tools


super telephoto mirror lenses


  • mirror lenses are difficult to use and for most people are probably not the best option
  • they were popular in the 1970's and 80's as they mainly competed against manual focus big, heavy, f/5.6-6.3 telephoto lenses
  • in the 1990's, the advent of new high refractive index glass, computerised lens manufacture combined with a now mature autofocus technology and optical image stabiliser, meant that mirror lenses were generally only for those whose budget could not afford a “real” telephoto lens such as a 400mm f/4 IS
  • catadioptric mirror lenses share the following characteristics:
    • fixed aperture
    • virtual elimination of chromatic aberration and lateral color fringes as uses mirrors 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 ugly “donut” shaped bokeh imagery in out of focus areas
    • front filter thread if present, rotates with focus
    • significant vignetting
    • difficult to suppress stray light, ghost and flare
    • shallow depth of field (DOF) with low contrast makes accurate manual focus difficult, further compounded on most lenses by the lack of micro-focus gearing so that only small incremental changes to focus can be made
  • apart from their telephoto reach for such a small size, these lenses were difficult to use for film photographers using SLR cameras as:
    • they usually had slow apertures around f/8 and were thus dim in optical viewfinders making manual focus difficult and requiring bright sunny conditions for any action shots
    • they were not image stabilised, and the light weight actually worked against getting sharp images without camera shake - even the camera's mirror was sufficient to cause camera shake

mirror lenses on mirrorless cameras

  • mirrorless camera systems cameras address many of the issues of mirror lenses by:
    • using an electronic view finder with magnified, image stabilised manual focus +/- manual focus peaking
    • no mirror to cause mirror-induced camera shake which is a big problem in SLRs and dSLRs at high magnification work such as when using these lenses
    • image stabiliser built-in such as the Olympus Micro Four Thirds system
    • Micro Four Thirds system have cropped sensors which give twice the telephoto effect as they are 2x crop sensors
    • allow better image quality at high ISO levels to ISO 1600 which partly addresses the f/8 aperture issue
    • post-processing of digital images can improve the lower contrast levels these lenses give
  • the Carl Zeiss Contax 500mm f/8 is said to be the sharpest with best contrast but these are also the most expensive and are quite rare
  • if small size, light weight and high image quality are your main requirements, then the Olympus OM 500mm f/8.0 mirror lens and the Minolta Rokkor RF 250mm f/5.6 mirror lens are the clear winners
  • However, on a Micro Four Thirds system camera, a 500mm f/8 mirror lens will be 1000mm f/8 and you should weigh this up against use of refractor style lenses such as:

mirror lenses


1000mm or more




cheaper designs

comparison of 500mm mirror lenses

model aperture diam length length incl. MFT adapter weight optics close focus front filter Infinity on Canon EOS
Olympus OM f/8 81mm 97mm 123mm 590g v. good 4m 72mm YES
Canon FD f/8 90mm 148mm 170mm 705g v.good 4m none NO
Nikkor N f/8 89mm 116mm 143mm 823g v. good 1.5m 82mm YES
Nikkor C f/8 93mm 142mm 169mm 1000g good 4m 88mm YES
Sony/Minolta f/8 89mm 118mm 142mm 665g v. good 4m 82mm NO
Tamron SP f/8 f/8 84mm 92mm mm 595g good? 1.7m 82mm YES
Samyang f/8 f/8 77mm 88mm 123mm 320g avg? 1.7m 72mm YES
Samyang f/6.3 f/6.3 119mm 98mm 133mm 705g avg? 2m 95mm YES
ProOptic Maksutov f/5.6 105mm 220mm 255mm 1220g good 1.5m slow but microtune none YES
photo/lensmirror.txt · Last modified: 2014/05/18 10:03 by gary1