Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 75,684   Posts: 1,669,368   Online: 772
      
Page 1 of 3 123 LastLast
Results 1 to 10 of 28
  1. #1

    Join Date
    Jan 2005
    Shooter
    Plastic Cameras
    Posts
    888
    Images
    5

    50mm Distagon vignettering

    Langzaam beginnen de eerste resultaten met m'n distagon "binnen te komen". Klopt het dat dit objectief vooral bij een grote diafragma-opening (met originele zonnekap, maar zonder filters en dergelijke voor de lens) vignetteert? Bij F/4 en F/5.6 krijg ik vaak donkere hoeken... is dat groothoek-eigen? Ik dacht dat een Zeiss objectief er minder last van zou hebben...

  2. #2

    Join Date
    Nov 2006
    Shooter
    4x5 Format
    Posts
    977
    bedoel je licht afval of echt vignettering ?
    In 't eerste geval. De optische wetten gelden ook voor Zeiss
    Mijn 40 op de hassie had in ieder geval weinig last van vignettering. http://www.xs4all.nl/~hamses/venster.jpg
    opgenomen met 5,6

  3. #3

    Join Date
    Jan 2005
    Shooter
    Plastic Cameras
    Posts
    888
    Images
    5
    Quote Originally Posted by Stever View Post
    I hope you translate this to English so that I could participate in this discussion.

    Steve
    The question was (in short): After investigating the first images of my recently aquired 50mm distagon, I am wondering whether it is "normal" for this Zeiss lens to show "darker corners" when the aperture is wide open (F/4 and F/5.6). I will try to show some scans of colour material later on this week(end)... to show what I mean.

  4. #4

    Join Date
    May 2006
    Location
    Northern Aquitaine
    Shooter
    35mm RF
    Posts
    4,913
    Quote Originally Posted by SoulSurround View Post
    The question was (in short): After investigating the first images of my recently aquired 50mm distagon, I am wondering whether it is "normal" for this Zeiss lens to show "darker corners" when the aperture is wide open (F/4 and F/5.6). I will try to show some scans of colour material later on this week(end)... to show what I mean.
    Thanks for summarizing it in English: I thought I had the Dutch right but wasn't sure.

    Yes it is. Look at the Zeiss spec sheets. You need f/8 or so to reduce vignetting to negligible levels -- though quite honestly, exposure needs to be pretty minimal, with transparency (not colour neg, where you can afford generous exposure) for the vignetting to matter much. I've just sent back the Distagon (and 120 Makro-Planar and 180 Sonnar) after borrowing for a 'road test'. My review will appear in due course in Shutterbug; Frances's will appear in Black and White.
    Free Photography Information on My Website
    http://www.rogerandfrances.com

  5. #5

    Join Date
    Jan 2005
    Shooter
    Plastic Cameras
    Posts
    888
    Images
    5
    Quote Originally Posted by Roger Hicks View Post
    Exposure needs to be pretty minimal, with transparency (not colour neg, where you can afford generous exposure) for the vignetting to matter much.
    That sounds plausible, as the vignetting was most obvious in photos made inside my house (on transparency material). I will run some more tests in the future to see whether this holds up.
    This lens is kind of intended to be my "holiday-lens"... you know, to get the whole picture of attractive scenes. But after seeing the vignetting I was kind of put-off by it. But the fact that this lens will probably be used outside the house 90% of the time, I will give it another go... before I think of selling it again.

    By the way, is it likely for one distagon to vignet more than another... in other words: can there be significant vignetting differences between lenses in the same series?
    Last edited by SoulSurround; 09-14-2007 at 12:53 AM. Click to view previous post history.

  6. #6

    Join Date
    Mar 2004
    Location
    Southern California
    Shooter
    Multi Format
    Posts
    3,879
    Images
    11
    Quote Originally Posted by SoulSurround View Post
    By the way, is it likely for one distagon to vignet more than another... in other words: can there be significant vignetting differences between lenses in the same series?
    Unlikely. This phenomenon follows the fundamental principles of geometric optics - the reduction in relative illuminance closely approximates the fourth power of the cosine of the angle by which the object point is off the camera axis (measured in "object space" at the center of the entrance pupil of the lens).

    My 50mm Zeiss Distagon images show cosine 4th illumination falloff and so do images made with my 50mm MC Zeiss Flektagon, plus my 65mm and 45mm Schneider Super Angulons, my 55mm Apo Grandagon and my 110mm Schneider Super Symmar XL (it gives especially obvious illuminance falloff towards the edges of an 8x10 negative). If you don't like the effect, you can use one of the special compensating Schneider or Zeiss filters.
    Tom Hoskinson
    ______________________________

    Everything is analog - even digital :D

  7. #7

    Join Date
    Jan 2005
    Shooter
    Plastic Cameras
    Posts
    888
    Images
    5
    Quote Originally Posted by Tom Hoskinson View Post
    If you don't like the effect, you can use one of the special compensating Schneider or Zeiss filters.
    I never heard of those... what are they called? Wide-angle-light-fall-off-compensation-filter-s?

  8. #8
    David H. Bebbington's Avatar
    Join Date
    Dec 2004
    Location
    East Kent, United Kingdom
    Shooter
    Medium Format
    Posts
    2,364
    Images
    36
    Quote Originally Posted by SoulSurround View Post
    I never heard of those... what are they called? Wide-angle-light-fall-off-compensation-filter-s?
    Yes, if you like! Alternatively - center graduated filter.

    Regards,

    David

    PS: This term is not good enough for Schneider - they say "concentrically graduated center filter" (and charge big $$$ accordingly):
    http://www.teamworkphoto.com/index.p...ducts_id=12143
    Last edited by David H. Bebbington; 09-14-2007 at 07:58 AM. Click to view previous post history.

  9. #9

    Join Date
    Nov 2006
    Shooter
    4x5 Format
    Posts
    977
    Een center filter is bedoeld voor licht afval veroorzaakt door de genoemde cos 4e orde enz. Deze is onafhankelijk van 't gekozen diafragma. Nu zal 't ook wel werken tegen de licht afval bij grote diafragma's. Maar is nogal contra produktief door zijn verlengings factor 2X - 4X. Immers dan kun je ook gewoon diafragmeren .

  10. #10
    Willie Jan's Avatar
    Join Date
    Jun 2004
    Location
    Best/The Netherlands
    Shooter
    4x5 Format
    Posts
    1,924
    Images
    49
    Een groothoek lens heeft lichtafval doordat het middenpunt relatief dichter bij de lens zit dan de rand (%).

    Echter hetzelfde treedt op bij een vergrotingsobjectief en net tegengesteld.

    Je negatief heeft te weinig dekking aan de randen.
    Dit negatief zal bij een bepaalde belichting aan de randen te veel licht doorlaten. Echter doordat de vergrotingslens weer lichtafval heeft aan de randen, wordt dit weer gecompenseerd....

    Dus tot een bepaald groothoek formaat heb je helemaal geen center filter nodig is mijn ervaring....

Page 1 of 3 123 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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