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    Re: Simplified Bris Sextant
    From: Alexandre Eremenko
    Date: 2012 May 7, 23:15 -0400

    I have to say that I do not find this Bris very practical.
    It is rather a toy than a navigation device.
    The reason is that you have to wait for these pre-assigned moments,
    there are few of them during the day, and at these moments
    Sun can be obscured by a cloud, or you can be busy with something
    else, or just miss the moment.
    I am interested to hear from a list member who managed to
    gratuate his/her Bris sextant:-)
    On Mon, 7 May 2012, Greg Rudzinski wrote:
    > Making a simplified Bris  Sextant only requires gluing two microscope slides 
    together with a gap at one end. The larger the gap the greater the angular 
    deflection of the reflected Sun. I used a 0.7 mm pencil lead to set a gap and 
    got 1* 57.8' of deflection. Inspect the linked image and you will see that 
    the reflected image is the sum of four images one on top of the other. This 
    must be from the front and back surface reflections from each slide. The best 
    a navigator can probably hope for is 1' to 2' of precision on a home made 
    version. Still this is pretty good for something that can get lost in a shirt 
    > Greg Rudzinski
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    > > > > > Attached File: http://fer3.com/arc/img/119461.f1-img_1189.jpg > > > View and reply to this message: http://fer3.com/arc/m2.aspx?i=119461 > > >

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