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    Re: Bris Confusion
    From: Greg Rudzinski
    Date: 2015 Jun 25, 09:19 -0700


    It looks like you have made a very sturdy Bris that should provide many reflected Sun images to calibrate. You will have to jocky the Bris around to find the low point for the Sun. Time when on the horizon then reduce all the way backwards to get an Hs. This will be your calibration angle for that particular reflection. Make up a cheat card with the reflections numbered and their calibration angles.

    Lots of posts in the archives.


    Greg Rudzinski

    From: Marty Lyons
    Date: 2015 Jun 25, 08:29 -0700

    I read the archived articles on the Bris, somewhat confusing. Pretty fascinating though, so I made one. I used three glass welding shields, two clear and one #5 shaded, spaced at slightly different angles.

    My questions are:

    1. Is the light supposed to enter the Bris from the top, in the spaces between the glass or through the back of the shade?

    2. I see what I think are a bunch of reflections. I will say, 1 bright, 2 less bright, 4 dimmer yet and on very dim. Is that correct?

    3. So to understand the principle, I sight the horizon and wait until one of the images comes down or up to the horizon and time it?

    4. I then work the sight backwards, using either manual methods or software solutions?

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