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  1. #11
    JBrunner's Avatar
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    Quote Originally Posted by rob champagne View Post
    Its only a very approximate measure because it ignores pupil magnification. The actual aperture is the size of the exit pupil which you can't see as it's hanging in space inside the lens. Its not the physical size of the iris.
    What, you mean I can't use these measurements to focus a friggin laser beam for shooting down an incoming ICBM? Oh, and we haven't even begun to factor in tortellini variance......:rolleyes:

  2. #12

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    Quote Originally Posted by rob champagne View Post
    Its only a very approximate measure because it ignores pupil magnification. The actual aperture is the size of the exit pupil which you can't see as it's hanging in space inside the lens. Its not the physical size of the iris.
    right...it worked fine with my simple slide projector lens, my 40/f1.8 lens...but not with the 28/f3.5

    thanks

  3. #13

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    tortellini variance?

    geez....I just get a handle on lorentzian linguini effects and you bring up tortellini variance?

    give a brother a break will ya?

  4. #14

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    Quote Originally Posted by JBrunner View Post
    What, you mean I can't use these measurements to focus a friggin laser beam for shooting down an incoming ICBM? Oh, and we haven't even begun to factor in tortellini variance......:rolleyes:
    Nope you can't. But I was merely explaining why the poster didn't get the results he expected from the method as described.

  5. #15
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    I probably wouldn't bother to try it on a modern multi element lens. Those generally aren't a mystery. It is an effective way to get in the ballpark with old unknown barrell lenses, such as I have. In my experience it gives enough of an approximation with these old lenses to have a usable stop. Bracket exposures from the approximation to fine tune, and you are happily using your old lens.

  6. #16

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    K...that's pretty much what I thought....

    still confused about the tortellini variance thing

  7. #17
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    Quote Originally Posted by DarkroomExperimente View Post
    K...that's pretty much what I thought....

    still confused about the tortellini variance thing
    Well, I'm still working on the math. I haven't been able to determine if tortellin variance is constant enough to be averaged. I'm afraid I ate the test sample, so until I get some more, we are all in the dark. And George, you are correct, they were parmesan...

  8. #18
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    Quote Originally Posted by JBrunner View Post
    Well, I'm still working on the math. I haven't been able to determine if tortellin variance is constant enough to be averaged. I'm afraid I ate the test sample, so until I get some more, we are all in the dark. And George, you are correct, they were parmesan...
    Not to forget the critical measurements depending upon the type and "state" of the tortellini.

    Firstly, was the tortellini a "fresh" specimen or was it "frozen" or, yet, if you use the Barilla-brand variant - a "dried" one?

    Then, you have to consider - based on which version you begin with - was the tortellini then "cooked"?

    This is a critical determination as a "cooked" tortellini will have a variant shape and size from an "uncooked" one - regardless of it's initial fresh/ fresh-frozen/ dried state (see above) base constants.

    And then, one must factor into the equation the "satiation effect".

    Did JB consumed a satiating portion of tortellini before conducting his focal lenght measurements such that he was not tempted to "nibble" small portions from either the posterior or anterior ends of some or all of the tortellini used in the experimental setting?

    The quantitative and subjective factors may have considerable bearing on JB's initial findings and thus requires he continue his experiments while applying the Greek classical measuring tools of the dolmades (stuffed grape leaves) and Kalamata olives!
    Last edited by copake_ham; 01-16-2008 at 11:19 PM. Click to view previous post history.

  9. #19

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    Reimannian Tortellini have a distinctive non-Euclidean geometry which can alter linear measurements

  10. #20
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    Theres the whole water going down the drain the other way in the southern hemisphere. This will affect the pasta making, which in turn affects the 'handedness' of the macaroni - the traditional right hand rule, becomes a left handed rule (in order to determine the flux, which you dont need anyway ... for anything) - not that hard once you learn to play the saxophone.

    Recent experiments by the folk at Cern with the LHC determined that Marco Polo was a fine chap and the 1/100000000 chance of it spontaneously developing a Death Star in orbit were unfounded.

    It been suggested its actually just the most expensive crop circle ever...

    Cleared the bowel problem, working on the consonants...

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