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    Re: Making an artificial horizon
    From: Greg Rudzinski
    Date: 2014 Jun 3, 10:32 -0700


    For this morning an artificial horizon of the Sun was made using a C&P Plath and no scope. A 50mm DSLR was used to capture the observation/UT . Uncomfortable flashes were reduced by removing the scope and shading the sextant mirrors correctly before attempting the observation. The AH was covered by the filtered horizon mirror then a search for the Sun was made. Now bring down the filtered Sun using the index arm. Finally fine adjust with micrometer. At this point the scope can be installed. I haven't noticed that much of an improvement in accuracy using the scope.

    The sight was reduced by the Ix cosine sum method. For those attempting to use this new reduction method be careful when dividing the quad cosine sum by 4. This is where I seem to blunder.

    Greg Rudzinski

    Re: Making an artificial horizon
    From: Noell Wilson
    Date: 2014 Jun 2, 06:30 -0700
    I think that Alan’s comment suggests a valuable possibility – put the dark shades on the AH, save your eyes, and don’t use the sextant shades.

    I’ve developed a real fear of my 6” square AH and the single, or double, flashes of direct sunlight that keep sneaking through.

    Right now I put the AH on top of a silver car. I’ve had to cut a big piece of cardboard to block the reflections off the car and wear dark glasses that help but are not in the same league with the noon sun(s) in Georgia.
    Now I’m thinking in terms of a No. 12 welding shade with opaque side shields to completely block the sun as long as you didn’t look over the top of the shade. I’d have to shrink the mirror size and get closer for a wide field of view but that’s not all bad.

    I’m apologize if someone has already mentioned this and I missed it.
    Regards, Noell
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