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    Re: (Fwd) The Most Anomalous Refraction Yet or What ?
    From: George Huxtable
    Date: 2009 Aug 4, 20:02 +0100

    > Greg Rudzinski wrote-
    > "Even just the camera held to a single pane window surface and cocked
    > slightly would create multiple reflections."
    And I had commented-
    > Not if the glass itself has its surfaces parallel, in which case, for an
    > object seen at infinity, the two images coalesce exactly, just as they do
    > in
    > the case of the two reflections from a back-silvered sextant mirror.. Such
    > a
    > displacement as Greg describes calls for some degree of "wedginess"
    > between
    > the surfaces.
    Now Greg replies-
    "If you can get your hands on a DSLR digital camera with a clear UV
    filter screwed snug to the lens then look through the view finder at a
    bright desk lamp through a window with the front of the lens touching
    the window and tilted to one side or the other then you will see the
    displacement effect. "
    Yes, indeed you will, in the case of the close-by desk lamp. But not in the
    case of an object at infinity, such as the Sun (as I wrote).  Greg should
    try the experiment to see.
    contact George Huxtable, at  george@hux.me.uk
    or at +44 1865 820222 (from UK, 01865 820222)
    or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
    NavList message boards: www.fer3.com/arc
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