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  1. #41

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    Wide-angle: the Achilles' heel of SLRs?

    David,
    Nikon came out with an excellent wide-angle lens, similar to the Zeiss Biogon in design (although with a slightly reversed formula), which you can see at http://www.mir.com.my/rb/photography...wides/21mm.htm .

    Unfortunately, this gem cannot be used on any but the more pro-line cameras, that offer MLU. That negates the "reflex" advantage, requiring a separate viewfinder and zone focusing.

    While this neither confirms nor defeats the "Achilles' Heel" premise, it does allow for an adaptation that works.

    Dan

  2. #42

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    Quote Originally Posted by barzune View Post
    David,
    Nikon came out with an excellent wide-angle lens, similar to the Zeiss Biogon in design (although with a slightly reversed formula), which you can see at http://www.mir.com.my/rb/photography...wides/21mm.htm .

    Unfortunately, this gem cannot be used on any but the more pro-line cameras, that offer MLU. That negates the "reflex" advantage, requiring a separate viewfinder and zone focusing.

    While this neither confirms nor defeats the "Achilles' Heel" premise, it does allow for an adaptation that works.

    Dan
    That lens was developed for the Nikon rangefinder cameras, then adapted to the SLRs. It was replaced with the 20/3.5 Nikkor UD, a big, heavy, and superb lens which does not require MLU. The Nikkormat Ft, FtN, and some others offered MLU.

  3. #43
    benjiboy's Avatar
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    Quote Originally Posted by Michael R 1974 View Post
    Being aware of and/or interested in how things work does not make someone any less a photographer, nor does it make someone a "wanker" of any kind. The wankers post to technical threads to remind everyone photography is about pictures. Brilliant.
    I've been involved in photography for more than fifty years and in my experience very few of the many photographers I have ever known who were obsessive testers of their equipment and darkroom chemicals and processes ever took a worthwhile photograph, their raison d'être was the testing, more often than not producing technically perfect images with little or no meaning or soul in them.
    Ben

  4. #44
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    Quote Originally Posted by Michael R 1974 View Post
    OP asked a technical question. I responded with a technical answer. Distortion is a practical difference between most RF and SLR wide angle lenses. Distortion is not typically a problem in landscapes but for those of us who often shoot subjects with straight lines parallel to the the edges of the frame distortion is visible and distracting. It has nothing to do with test charts and graph paper. Sorry.
    I totally agree.

    There are circumstances, taking pictures of architectural features, where straight lines are important and distortion, if present, can be very evident and quite disturbing.

    https://www.zoonar.com/photo/detail-...me_830873.html

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  5. #45
    benjiboy's Avatar
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    Quote Originally Posted by Diapositivo View Post
    I totally agree.

    There are circumstances, taking pictures of architectural features, where straight lines are important and distortion, if present, can be very evident and quite disturbing.

    https://www.zoonar.com/photo/detail-...me_830873.html

    http://www.alamy.com/thumbs/6/%7B6AC...%7D/BDE8MM.jpg

    http://www.alamy.com/thumbs/6/%7B784...%7D/BWNKAA.jpg
    These distortions are a red herring, because they not because of inherent lens aberrations but because the camera has been pointed upwards to cause perspective distortion because it wasn't capable of lens movements in relation to the film plane.
    Ben

  6. #46
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    Quote Originally Posted by benjiboy View Post
    These distortions are a red herring, because they not because of inherent lens aberrations but because the camera has been pointed upwards to cause perspective distortion because it wasn't capable of lens movements in relation to the film plane.
    Yep.
    Mark Barendt, Beaverton, OR

    "We do not see things the way they are. We see things the way we are." Anaïs Nin

  7. #47
    Ian Grant's Avatar
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    I have to agree with Michael R

    Quote Originally Posted by Michael R 1974 View Post
    Being aware of and/or interested in how things work does not make someone any less a photographer, nor does it make someone a "wanker" of any kind. The wankers post to technical threads to remind everyone photography is about pictures. Brilliant.
    The OP asked a valid question and there's no doubting that the best extreme WA lens sdesigns have been made fo rangefinder cameras and aren't made for SLR use (unless mirror lock is used).

    That doesn't mean that there aren't good extreme wide angles for SLR use, it's just that they behave slightly differently. If they weren't there would be no need for Hasselblad to have made the SWC cameras, Nikon their special 2.1cm f/4-16 Nikkor-O etc.

    The OP's asking about those differences and unless you've used both types of designs it is hard to appreciate the benefits of the purer designs of wide angle lenses for rangefinder cameras, or in the case of the SWC and Nikon lens where no mirror is used.

    Ian

  8. #48
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    Originally Posted by Diapositivo View Post
    I totally agree.

    There are circumstances, taking pictures of architectural features, where straight lines are important and distortion, if present, can be very evident and quite disturbing.
    Quote Originally Posted by benjiboy View Post
    These distortions are a red herring, because they not because of inherent lens aberrations but because the camera has been pointed upwards to cause perspective distortion because it wasn't capable of lens movements in relation to the film plane.
    Actually benjiboy is incorrect. Diapositivo was referring to barrel or pincushion distortion, where straight lines bend due to lens distortion.

    Converging verticals, a result of the angle of the camera, is not 'distortion', it is just perspective. The lines of a building will still be perfectly straight.
    Go not to the elves for counsel, for they will say both yes and no.

  9. #49
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    Quote Originally Posted by Ian Grant View Post
    That doesn't mean that there aren't good extreme wide angles for SLR use, it's just that they behave slightly differently. If they weren't there would be no need for Hasselblad to have made the SWC cameras...
    It should be kept in mind by all that the Biogon 38mm on the Hassy SWC was designed back in a day when retrofocus lenses indeed had design limitations in portrayal of rectilinear features without considerable barrel distortion, while the first version 40mm Distagon for the SLR exibitied distortion quite considerably. Later Hasselblad updated with a newer 40mm Distagon, which was a notably sharper lens than the older Biogon and which also greatly reduced lens abberations in spite of its retrofocus design.

    Similarly, it used to be that zoom lenses were considerably inferior to fixed FL lenses, back when computers were not used for lens design. Today's zoom lenses often rival and even exceed the performance of even fixed FL lenses which have not been updated in the optical formula with newer computerized designs.

    In short, what used to be true is not always still true today!

  10. #50

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    Quote Originally Posted by markbarendt View Post
    The big problem with technical discussion is agreeing on the criteria to use as "the" standard.

    A technical best can only be determined when the output requirements are defined.

    If "pictures" means "artistic fun stuff for my walls" is the defined output there is one standard.

    If "pictures" means essentially "technically accurate representations of a scene" the standard is quite different.

    Us wankers can pick our own standards.
    You can pick whatever standard you like. I'm pointing out to OP that most SLR wide angle lenses exhibit visible distortion around the edges, that it is inherent in their designs and is difficult to correct, although some are much better than others. Like it or not that is an optical compromise. Perhaps "Achilles Heel" is the wrong title for the thread since it assumes SLR wides are inferior overall from an image-making perspecitve. Nobody ever said that. I use them myself rather than RF lenses. Distortion is only one property of a lens, and when it comes to that particular property RF wides generally perform better than SLR wides. This is what OP asked about.

    Why some snob has to chime in to a 35mm equipment forum to say anyone who cares about distortion is a "gadget wanker" is beyond me. Some great photographers have had an interest in how their tools work. And there are also millions of shit photographers who have no interest in equipment.
    Last edited by Michael R 1974; 11-19-2012 at 12:06 PM. Click to view previous post history.

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