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  1. #1
    baachitraka's Avatar
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    Lens with two apertures

    As you might have experienced that squinting human eye can able to see outside world slightly sharper...

    With that, Will adding an another aperture to an existing lens produces any sharper pictures, provided both apertures have same or different opening?

    Just curious...
    OM-1n & OM-2sp : 35, 85 and 135mm Zuikos.

  2. #2
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    That's what a ND filter is for.....

  3. #3
    baachitraka's Avatar
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    Quote Originally Posted by mrred View Post
    That's what a ND filter is for.....
    There is already a design available from Sony with two apertures.

    http://www.the135stf.net/design.html
    Last edited by baachitraka; 06-22-2011 at 05:41 AM.
    OM-1n & OM-2sp : 35, 85 and 135mm Zuikos.

  4. #4
    tomalophicon's Avatar
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    Would a stereo camera fit the bill? Or is the 2 aperture idea more effective in one lens?

  5. #5
    baachitraka's Avatar
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    Quote Originally Posted by tomalophicon View Post
    Would a stereo camera fit the bill? Or is the 2 aperture idea more effective in one lens?
    At-least from Minolta's design(now SONY) looks great.
    OM-1n & OM-2sp : 35, 85 and 135mm Zuikos.

  6. #6
    markbarendt's Avatar
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    The Sony lens is a soft focus lens, not a super sharp lens.

    Mamiya and others have done this for years.

    They don't provide sharper or less sharp images, soft focus lenses treat the out of focus areas differently.

    In the Mamiya 150SF for the RB for example, the glass is designed with spherical aberrations that affect the image when an f stop larger than f/8 is used. (At f/8 and smaller apertures the lens is "normal".) The lens originally came with 3 disks with many small holes around a normal aperture opening.

    These disks allow a user to adjust to f/5, f/5.6, or f/6.3 while leaving the normal aperture control at f/4, the extra holes scattered around the main aperture allow the aberrations to "sneak in" around the edges.

    This is one of my favorite lenses. This lens requires working differently, like stoping down to f/8 to focus and taking the lens apart to set aperture. It's effects are also strongest in the highlights.
    Mark Barendt, Ignacio, CO

    My aspiration of late is to become more Bohemian; "a person with artistic or intellectual tendencies, who lives and acts with no regard for conventional rules of behavior."

  7. #7
    baachitraka's Avatar
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    ...but, the samples look okay for me.

    http://www.the135stf.net/samples2.ht...iky_Planet.jpg

    I am not a fanboy of SONY but just wondering what effect will bring on image quality when two or more apertures are used.


    Quote Originally Posted by markbarendt View Post
    The Sony lens is a soft focus lens, not a super sharp lens.

    Mamiya and others have done this for years.

    They don't provide sharper or less sharp images, soft focus lenses treat the out of focus areas differently.

    In the Mamiya 150SF for the RB for example, the glass is designed with spherical aberrations that affect the image when an f stop larger than f/8 is used. (At f/8 and smaller apertures the lens is "normal".) The lens originally came with 3 disks with many small holes around a normal aperture opening.

    These disks allow a user to adjust to f/5, f/5.6, or f/6.3 while leaving the normal aperture control at f/4, the extra holes scattered around the main aperture allow the aberrations to "sneak in" around the edges.

    This is one of my favorite lenses. This lens requires working differently, like stoping down to f/8 to focus and taking the lens apart to set aperture. It's effects are also strongest in the highlights.
    OM-1n & OM-2sp : 35, 85 and 135mm Zuikos.

  8. #8
    markbarendt's Avatar
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    Quote Originally Posted by baachitraka View Post
    ...but, the samples look okay for me.

    http://www.the135stf.net/samples2.ht...iky_Planet.jpg

    I am not a fanboy of SONY but just wondering what effect will bring on image quality when two or more apertures are used.
    Like I said the 150SF is a favorite of mine. I like the SF effect.

    The central aperture controls the main/sharp image.

    The filtered area, by holes or whatever around the main aperture, allows the effect, whatever that may be, of the rest of the edges of the glass to be used.
    Mark Barendt, Ignacio, CO

    My aspiration of late is to become more Bohemian; "a person with artistic or intellectual tendencies, who lives and acts with no regard for conventional rules of behavior."

  9. #9
    baachitraka's Avatar
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    [QUOTE=In the Mamiya 150SF for the RB for example, the glass is designed with spherical aberrations that affect the image when an f stop larger than f/8 is used. (At f/8 and smaller apertures the lens is "normal".) The lens originally came with 3 disks with many small holes around a normal aperture opening[/QUOTE]

    Curious to look any sample pictures.
    OM-1n & OM-2sp : 35, 85 and 135mm Zuikos.

  10. #10
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    I have some rough negative scans:
    Attached Thumbnails Attached Thumbnails img072.jpg   img047.jpg  

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