A&P macro shots v. Sigma 105mm f/2.8 DG macro

Discussion in 'Lifestyle' started by themolsen, Sep 22, 2008.

  1. themolsen

    themolsen New Member

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    test shots taken on a Nikon D50 body

    Pretty sweet lens. doesn't do so hot in autofocus mode (hunts a lot), but that's ok. f/2.8 = super thin DOF. makes for some really awesome shots. the lens is really sharp too - even wide open!

    but can someone please explain this to me? when I'm focused at the closest, 1:1, why does it say the f-stop is f/5.6 event though it's f/2.8.... but not...or something....? all of these were shot wide open, but the closer I focus, the higher it says the f-stop is

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    razor-thin DOF:
    [​IMG]

    [​IMG]
     
    Last edited: Sep 22, 2008
  2. Bloke

    Bloke Banned

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    the goal of macro isnt to shoot wide open all the time, as you can see you arent even getting your whole subject.
     
  3. GlobeGuy

    GlobeGuy New Member

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    .
     
  4. themolsen

    themolsen New Member

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    I should have clarified - this were meant to be test shots of the extreme of the lens' capabilities. thus I shot them all wide open. i know how to take proper photos lol

    although, I would have shot #1 and #3 that way anyway
     
  5. wrong1

    wrong1 Member

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    Macro lenses lose aperture as they magnify. If they were 2.8 all the way through they'd have to be huge.
     
  6. xenon supra

    xenon supra OT Supporter

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    holy crap :eek3:
     
  7. mobbarley

    mobbarley Active Member

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    wat
     
  8. wrong1

    wrong1 Member

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    I know he is talking about a sigma, but the same rule applies.

    Here is a link to a discussion on it.

    http://www.nikonians.org/forums/dcboard.php?az=show_topic&forum=146&topic_id=13313


    I had noticed the same thing on my 60 2.8, I thought something was wrong with it...
     
  9. Bloke

    Bloke Banned

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  10. themolsen

    themolsen New Member

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    honestly. at 1:1, f/5.6, there's so little DOF, i don't complain about it not actually being f/2.8
     
  11. wrong1

    wrong1 Member

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    :werd:

    and :werd:
     

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