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Snowflake macro (double om zuiko 50)

Discussion in 'Other Genres' started by Vivalo, Feb 3, 2011.

  1. Vivalo

    Vivalo Olympus Loser

    931
    Nov 16, 2010
    Finland
    Here's one macro shot from yesterday. Taken with OM Zuiko 50 1.4 and OM Zuiko 50 1.8 attached to it reversed. Handheld, F/5.6, iso 1000, 1/60 sec. Exact 1:1 macro ratio, I suppose.

    Original camera jpeg

    P2025765.JPG



    Edited jpeg

    P2025765_copy.



    The equipment

    Zuiko_50_macro.JPG



    And another 1:1 macro shot

    [​IMG]


    Regards
    Ville
     
    • Like Like x 6
  2. Vivalo

    Vivalo Olympus Loser

    931
    Nov 16, 2010
    Finland
    Any thoughts what the focal length is when two 50mm lenses are together nose to nose? :confused:

    I was wondering that when I set the mms to the IBIS. I ended up to 50mm.
     
  3. akulya

    akulya Mu-43 Veteran

    249
    Jun 21, 2010
    Awesome pictures, and amazing lenses!

    Calculating the focal length would use a rearrangement of the formula I found here

    my (perhaps wrong, anyone want to check my maths?) answer is....

    f = d / [2(1+m/p)tan{2alpha}]

    where...
    "f" = focal length
    "d" = measured linear dimension for the angle your using (i.e. if you are measuring the horizontal angle fo view, this number is the horizontal length of the sensor = 17.3mm)
    "m" = magnification (with 1 being eqiv to 1:1)
    "p" = ratio of apparent exit pupil diameter : entry pupil diameter
    "alpha" = angle of view (the angle of view for the distance "d")

    I'm not sure how you measure the apparent pupil diameters though...
    :) I like this game


    Code:
    incidentally my rearrangement went...
    
    alpha = 2arctan {d / [2f(1+m/p)]}
    
    2alpha = arctan {d / [2f(1+m/p)]}
    
    tan{2alpha} = d / [2f(1+m/p)]
    
    (1+m/p)tan{2aplha} = d / 2f
    
    d / (1+m/p)tan{2aplha} = 2f
    
    f = d / [2(1+m/p)tan{2aplha}]
    
     
    • Like Like x 2
  4. ~tc~

    ~tc~ Mu-43 Hall of Famer

    Oct 22, 2010
    Houston, TX
    the apparent pupil diameter is the apparent diameter of the aperture opening as seen through the front (entry) and the back (exit), and they are requiring the ratio, so it looks like the equation needs to know how much of the magnification is before the aperture opening and how much is after ... Wow, looks like a giant PITA to figure out an answer to a question that doesn't need to be asked since you don't need IS when shooting from a tripod anyways.
     
  5. Vivalo

    Vivalo Olympus Loser

    931
    Nov 16, 2010
    Finland
    The snowflake was shot handheld, that is why I was wondering the mms.
     
  6. DesertRose

    DesertRose Mu-43 Regular

    91
    Dec 1, 2010
    Colorado
    Wow! Love the snowflake shot!!
     
  7. walt_tbay

    walt_tbay Mu-43 Veteran

    322
    Aug 24, 2010
    Ontario, Canada
    Awesome snowflakes!
     
  8. Way back in time I made a macro lens coupler from two appropriate diameter Cokin screw mounts glued face to face with crazy glue; 10 years later it is still holding together. Another option is a worm screw clamp if the lens are the same diameter, got that hint from a Popular Photography or Mechanics magazine.
     
    • Like Like x 1
  9. penfan2010

    penfan2010 Mu-43 All-Pro

    Nov 12, 2010
    NJ, USA
    Vivalo - way cool, thanks for sharing. I was just about to ask you where you got the reverse lens adapter before I looked at the set up...nice one.