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    Re: Use of AH for professional navigation
    From: Byron Franklin
    Date: 2011 Oct 7, 17:16 -0700

    Byron: SAIL MAGAZINE SEPT 89
    How to see at night
    The way you use your eyes at night is different from the way you use them during the day With normal day vision, you train your eyes to look directly at the target. If you catch something out of the corner of your eye, you automatically move your eyes to center on the target. Once you have done so, you can see the target clearly in detail. In the dark, however, instead of directing your vision at the area you desire to see, you must learn to use off-center vision.
    The first step in training yourself in night vision is finding a location free of normal white city lights, per haps your backyard. Wait until your eyes have adapted to the dark; this can take about 15 to 20 minutes. At this point the sky is black, the stars are bright, and you are aware of your surroundings. Your eyes are accustomed to the dark.
    Look at the sky and find a bright star. Now slowly move your eyes until you see, or think you see, the dimmest star out of the corner of our eve. Look directly at the star. if it is a very dim star it will “disappear when you look at it and won’t reappear until you move your eyes and “look” at it using the off-center technique. It may be fuzzy and lack color. But you see it with your peripheral vision.
    What is happening here is that you are seeing it with your peripheral vision. Practice this off-center technique until you are comfortable picking up even the dimmest star.
    Binoculars can help make some of the dimmer stars very bright. But other stars will disappear when you look directly at them, even with binoculars.
    At sea at night, relax and move your eyes slowly just a few degrees above the horizon. If you think you see a light, use the off-center vision technique to isolate your target. If the light is very faint and disappears, use a slow, off-center eye motion to pick it up again. Then use your binoculars to pick up any color details. Practice this off-center procedure until you are proficient in seeing things at night. When you are in the darkness, only a trained eye can produce the correct information quickly —Byron E. Franklin
    Byron Franklin spent 26 years as a Navy quartermaster aboard surface ships and nuclear

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