DPRevived & The Photo
  • Web Site
  • chevron_right Threads
  • label All Forums
  • label Discussion News and Discussions
  • label TQ Technical Discussions

Patents related to photographic lenses

Dibyendu
March 30, 2023
chat_bubble_outline 24
first_page chevron_left
first_page chevron_left
  • link
    bclaff
    Members 21 posts
    May 11, 2023, 11:52 p.m. May 11, 2023, 11:52 p.m.
    link

    Cosina Voigtlander Nokton 50mm F1.0 Aspherical
    snip.png

    snip.png

    PNG, 98.1 KB, uploaded by bclaff on May 11, 2023.

    Dibyendu likes this.

    favorite 1

  • link
    bclaff
    Members 21 posts
    May 24, 2023, 8:59 p.m. May 24, 2023, 8:59 p.m.
    link

    Fujifilm Fujinon XF8mm F3.5 R WR
    Fujifilm Fujinon XF8mm F3.5 R WR.png

    Fujifilm Fujinon XF8mm F3.5 R WR.png

    PNG, 137.4 KB, uploaded by bclaff on May 24, 2023.

  • link
    bclaff
    Members 21 posts
    May 25, 2023, 3:20 p.m. May 25, 2023, 3:20 p.m.
    link

    Canon New FD800mm f5.6L
    Canon New FD800mm f5.6L.png

    Canon New FD800mm f5.6L.png

    PNG, 175.1 KB, uploaded by bclaff on May 25, 2023.

  • link
    Dibyendu
    Members 139 posts
    May 26, 2023, 10:24 p.m. May 26, 2023, 10:24 p.m.
    link

    Cosina Voigtlander APO-SKOPAR 90mm F2.8 SL IIs ?

    patentscope.wipo.int/search/en/detail.jsf?docId=JP395479011

    www.cosina.co.jp/voigtlander/en/slr-mount/apo-skopar-90mm-f2-8-sl-iis/

    cosina-patent-apo-90mm.jpg

  • link
    bclaff
    Members 21 posts
    May 27, 2023, 2:48 a.m. May 27, 2023, 2:48 a.m.
    link

    Re; Cosina Voigtlander APO-SKOPAR 90mm F2.8 SL IIs ?

    Worth a look. Clearly related but the 4th element of the production lens looks much thicker.

  • link
    Dibyendu
    Members 139 posts
    May 27, 2023, 12:16 p.m. May 27, 2023, 12:16 p.m.
    link
    @bclaff has written:

    Re; Cosina Voigtlander APO-SKOPAR 90mm F2.8 SL IIs ?

    Worth a look. Clearly related but the 4th element of the production lens looks much thicker.

    Indeed, Cosina patents often do not exactly match the production lens. The 50mm f1 was a fortunate exception.
    I am also not sure how much of Cosina's claims re anomalous partial dispersion glasses are true, as the patent does not quite confirm that 5 out of 7 elements are of this type.

  • link
    bclaff
    Members 21 posts
    May 27, 2023, 5:39 p.m. May 27, 2023, 5:39 p.m.
    link
    @Dibyendu has written:

    Cosina Voigtlander APO-SKOPAR 90mm F2.8 SL IIs ?

    patentscope.wipo.int/search/en/detail.jsf?docId=JP395479011

    www.cosina.co.jp/voigtlander/en/slr-mount/apo-skopar-90mm-f2-8-sl-iis/

    cosina-patent-apo-90mm.jpg

    Yeah. Not really.
    Not Cosina Voightlander APO-Skopar 90mm F2.8.png

    Not Cosina Voightlander APO-Skopar 90mm F2.8.png

    PNG, 132.6 KB, uploaded by bclaff on May 27, 2023.

  • link
    bclaff
    Members 21 posts
    May 29, 2023, 9:14 p.m. May 29, 2023, 9:14 p.m.
    link

    Sigma 24mm F1.4 DG DN A
    Sigma 24mm F1.4 DG DN A.png

    Sigma 24mm F1.4 DG DN A.png

    PNG, 177.9 KB, uploaded by bclaff on May 29, 2023.

  • arrow_forward

    Thread has been moved from General Techniques and ideas.

    • By AlanSh on April 17, 2024, 10:42 a.m..
first_page chevron_left
arrow_upward Go to top
  • DPRevived.com is owned and operated by The Photographer's Foundation Limited, registered in England, company number 14795583. Email: management@DPRevived.com
powered by misago