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    Re: Astra IIIb: First Impressions
    From: Sean C
    Date: 2014 Mar 13, 08:43 -0700

    "With this sextant and an artificial horizon, you should expect intercepts (altitude errors) on the order of half a minute of arc or better straight out of the box. These numbers look like the result of an incorrect index correction." -FER

    You were right, Frank. I shot a couple Moon-Mars lunars and although I know I did a good job lining them up, they were 2.4' and 2.1' off. I think the problem is that after I adjusted the horizon mirror, I simply set the sextant to 0° 0' and checked to see if the images lined up. I should have run through the whole process of lining up the limbs again.

    Yesterday, out of curiosity, I set the sextant to 0 again and looked at the Moon. The images looked well aligned enough to me. I then set it to 0° 01.5' and looked again. The overlapped images appeared sharper. So, today I ran through the whole process with the Sun again and triple checked my adjustment. Twice by re-aligning the limbs and once by moving the drum until I could see the sharpest image. When I looked at where I had stopped, it was exactly at 0° 0'. Now I have to do some more sights, but it's chilly and very windy today so I might wait.

    -Sean C.
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