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    Re: (Fwd) The Most Anomalous Refraction Yet or What ?
    From: Greg Rudzinski
    Date: 2009 Aug 4, 12:18 -0700

    I just pulled out my DSLR and did the infinity experiment that you
    have proposed and a second reflective image of the Sun's image(not the
    primary image) gets displaced as I angle the glass to one way or the
    other resulting in two images of the sun with one bright and one dim.
    On Aug 4, 12:02�pm, "George Huxtable"  wrote:
    > > 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.
    > George.
    > contact George Huxtable, at �geo...@hux.me.uk
    > or at +44 1865 820222 (from UK, 01865 820222)
    > or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
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