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    Re: Using glasses when taking sights
    From: Frank Reed
    Date: 2013 May 13, 09:26 -0700

    You should remove your glasses and re-focus. The telescope's focus can handle normal optical corrections for near/far sightedness. The correction for near point or "reading" is not relevant to taking sights where the focus is at infinity, but then you have the problem of reading the micrometer. So keep your bifocals close at hand and use them for reading or get a common magnifying glass. You could even mount a magnifier on a tripod near your shooting location. If it's a few steps away, you take a sight, walk over and hold the sextant under the magnifying glass, record the sight, and then on to the next one. That might be less fumbling and less risk of dropping your eyeglasses. Another option, which has many merits, is video recording. Set up any modern digital camera or smartphone for video recording arranging for a short-range focus if possible. You start off a sight sequence by announcing the exact GMT or displaying it to the camera, then as you shoot, you call the moment and then hold the sextant up to the camera and then get right back to shooting. You don't record the time or read the angles as you go --they're in the video. At the end of the run, for good measure, you can announce the GMT again. Then, at your leisure, you can play back the recording, read off the exact time and also read the angle and micrometer directly from the video. Working like this, you can get sights every thirty seconds and maybe even a little faster. Just for practice, of course.

    -FER


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