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       Just flown back home to take a couple of weeks off and decided to practice a little more about my CN skills while staying at home. (staggering summer heat prevents one from forming any ideas to linger around under the sun, days are so hot that even taking a casual evening stroll on the street for ten minutes would get yourself completely drenched with sweat).  

      Since moon is practically full or over 90% full these days and with both of its limbs clearly visible, I reckoned that I ought to use this opportunity to do moon shots and re-check my IE, and eventually I did so for several consecutive days by shooting indoors through a Davis artificial horizon and the double-glazed window of my room.(I have some doubts about whether double-glazed glass would distort the light path a little bit）

       The sextant I have at home is a Tamaya 633 in almost prestine condition(albeit missing the fixture for the 12× scope). For a pure hobbyist I do own a couple of other sextants but they are all stored in my apartment near work, 2000 km away from me. This is the only one available at home. And it was given to me several year ago for free from a seafaring friend whose ship he served on was about to get scrapped at the time. It's a pretty good instrument I'd say but I'm still not quite content with the fact that it does not have a vernier scale.

       For the purpose of exploring the posssibility of using and determine the accuracy of a handmade vernier scale, I decided to make one myself. What happened after is that I removed the original zero line mark and scavenged some leftover model water decals from my workbench to be used as graduation lines of the vernier, after carefully trimmed the decals to the proper dimention, I soaked them with water and then applied them adjacent to the micrometer one by one.  The benefit of using water decals as graduations is that it allows you to make repeated fine adjustments,until you get a notch width that is just right. After several hours of work,I finally made a complete set of vernier scale that in theory should magnify the resolution of my sextant 5 times better, and provide a fine reading down to one fifth of an arc minute instead of one whole minute. The micrometer drum is then removed to re-align its zero mark with vernier zero mark as close as possible.  After that A thin film of gloss varnish is sprayed onto to the vernier to prevent itself from being wiped off accidentally thus wraps up the whole job. 

       After rechecking the ie,then come the sightings. I'm not familiar with sight reductions for the moon since I havent done any before. So I did all the height corrections manually and looked up tabulated corrections in the NA for cross reference. After solving the triangle with Pub229 and plotting, I found out that most LOPs fall within a 8 nm range with a perticular bad LOP that is 11 nm off(I took that sight with water surface constantly shivering). There're two good LOPs that fall within 3 nm,could be sheer luck, I'll put the worksheets for these two shots in the post.

 (I cannot obtain a proper fix since I stayed indoors and with trees and stuff obscuring my view I had only a very limited window of angle to shoot the moon therefore all the moon azimuth observed are consentrated in a south-easterly direction.)

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