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    Sextant vs. Camera Sea Trial
    From: Greg Rudzinski
    Date: 2012 Jun 12, 09:45 -0700

    This last weekend a sea trial was performed that compared 4 power, 7 power, whole horizon, split horizon, to a 50 mm lens on a single lens reflex digital camera. All instruments/camera functioned well and yielded intercepts no worse than 3 minutes of arc. The easiest to use was strangely the camera which captured images of the Sun with no more difficulty than on land. The difficult draw back to the camera was measuring an Hs pixel value with a pitching and rolling laptop. This procedure requires an iron stomach. The hardest observation to make was done with a 7 power scope viewed through a split horizon mirror. Finding the Sun in the field of view is a challenge which is then followed by an equally hard task of rocking the body to the low point. Much easier was the whole horizon equipped with a 4 power scope. Using a sextant without a scope is the easiest of all but trying to get the eyes to see a sharp limb tangent to the horizon made for an uncertain observation. I would have liked to try a 2 power scope on both the split and whole horizon. I don't think there are any aftermarket scopes available in this power. There might be a market among cruising sailors for the lower power scope.

    Greg Rudzinski

    P.S. In the linked image of the three Sun reflections is also observed a BBQ. Cruisers quickly find out that the sailboat is just an accessory to the BBQ. And yes the BBQ got tested too with New York strips timed to the second by chronometer ;-)
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