Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 69,989   Posts: 1,524,099   Online: 1098
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 14
  1. #1

    Join Date
    Aug 2005
    Location
    Earth
    Shooter
    Multi Format
    Posts
    1,560

    The largest aperture...

    While posting to the thread:

    "How much over exposure? or A-Max (a REALLY big apeture)"

    I started to wonder what the largest F/value ever produced was...

    I have used a wonderful but heavy 105mm (135mm?) 1.2 lens...
    but what are the practical and theoretical limits?

    How low can you go?


  2. #2
    Steve Smith's Avatar
    Join Date
    May 2006
    Location
    Ryde, Isle of Wight
    Shooter
    Medium Format
    Posts
    8,555
    Images
    122
    Canon had an f0.95 lens and Zeiss made an f0.7 for NASA.


    Steve.

  3. #3
    tony lockerbie's Avatar
    Join Date
    Feb 2006
    Location
    Bega N.S.W. Australia
    Shooter
    Multi Format
    Posts
    2,294
    Images
    373
    I would imagine that it was the Canon 0.95, that was fitted to the Canon 7. Leicas' F1 Noctilux goes close, and is a damn sight better. BTW, what was the 105mm 1.2 that you mention, the fastest 105 that I have seen is the 1.8 Nikkor.
    The other good one is Canons' 1.2 85mm.

  4. #4

    Join Date
    Sep 2007
    Location
    Richmond VA.
    Shooter
    Multi Format
    Posts
    6,742
    I have the 85mm 1.2 which is outstanding.

    Jeff

  5. #5
    RobertV's Avatar
    Join Date
    Mar 2009
    Location
    the Netherlands
    Shooter
    Multi Format
    Posts
    1,057
    Leica's -M new Noctilux (50mm) is 0,95 and over Eur. 8000,00.
    It's a good lens but the price difference of their Summilux 1,4/50mm is pretty big.

  6. #6
    tim_walls's Avatar
    Join Date
    Sep 2006
    Location
    Croydon & Leeds
    Shooter
    35mm
    Posts
    1,037
    Images
    48
    Quote Originally Posted by Jeff Kubach View Post
    I have the 85mm 1.2 which is outstanding.
    I'll second that - the 85mm/1.2L is a thing of beauty.

    I've been looking on Fleabay to see if I can pick up the FD mount version as well, but it seems they hold their value rather too well for my budget!
    Another day goes under; a little bourbon will take the strain...

  7. #7

    Join Date
    Aug 2005
    Location
    Earth
    Shooter
    Multi Format
    Posts
    1,560
    Quote Originally Posted by tony lockerbie View Post
    BTW, what was the 105mm 1.2 that you mention, the fastest 105 that I have seen is the 1.8 Nikkor.
    Good question...
    I don't know; certainly it was not from one of the big camera mfg... I got it either from 42st Photo or Freestyle, and did not expect much... but I was very happy with it...

    Unfortunately, it was stolen with a lot of other gear many years ago, and not being a name I knew, I have forgoten it.

  8. #8

    Join Date
    Jul 2007
    Location
    Netherlands
    Shooter
    Medium Format
    Posts
    5,686
    Quote Originally Posted by Ray Rogers View Post
    but what are the practical and theoretical limits?

    How low can you go?
    Theoretically, f/0.5. Or rather, just shy of f/0.5.
    Practically, a bit less. f/0.7 at best.

  9. #9
    Maris's Avatar
    Join Date
    Jan 2006
    Location
    Noosa, Queensland, Australia.
    Shooter
    Multi Format
    Posts
    714
    For lenses working in air the theoretical limit is not quite down to 0.5. The problem that intrudes and limits relative aperture is total internal reflection at the glass to air interface. A cone of rays promising an aperture larger than 0.5 can exist inside the glass of the lens but the peripheral rays just can't get out.

    If one designs a lens system so that the focal plane coincides with the surface of the rear lens element and one is prepared to oil a film to this surface (to keep the air out and keep total internal reflection at bay) then apertures wider than 0.5 can be delivered.

    A system resembling this, but with the light rays going in the reverse direction, is regularly used in high resolution oil-immersion microscopy.
    Photography, the word itself, invented and defined by its author Sir John.F.W.Herschel, 14 March 1839 at the Royal Society, Somerset House, London. Quote "...Photography or the application of the Chemical rays of light to the purpose of pictorial representation,..". unquote.

  10. #10
    ic-racer's Avatar
    Join Date
    Feb 2007
    Location
    Midwest USA
    Shooter
    Multi Format
    Posts
    6,134
    I think this was the fastest mass-produced 'consumer' lens: F 0.90 Switar. If someone knows anything faster, please post.


Page 1 of 2 12 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin