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    Aero-navigator getting use to the marine sextant and false horizon
    From: Howard G
    Date: 2022 Jan 1, 15:18 -0800

    Hi Folks

    Time for a laugh - on my account please - picture me trying out my new Davis 25 plastic sextant - trying to get my 1st shoot of the sun using my false horizon.

    Dam - I felt like a kid on my first date meeting someone for coffee - I was all fiddles and thumbs and ham fisted!!!!

    Here I was 2800 ft up in the Southern Highlands of New Sout Wales - Australia (East Coast - 120 km south of Sydney - about 40 km in land)

    My section of 1.2 acres is surrounded by 80 year old conifers and our house is 2 storey and the outside temp was 30 C.

    False horizon - bought from amazon - a fairly crude gadget - plastic box - fill with water - place 2 pieces glass over water ...... at this stage I really had no idea how the dam thing worked - so I sat it on our courtyard table which also had a beautiful shiny piece of glass on it ----- yep that took a while to click also!

    And I emerged with my Davis 25 (which I had taken to a picnic on the coast a few days ago - with the sun now west of me (as we arrived after lunch) and the horizon (Tasman Sea) due East - all I could do was just fiddle and learn to align - and get use to handling.

    So here I was at 11:30 local (GMT +11) at 34 deg 29' S (and the Winter Solstice had just passed so the sun was close to overhead) - and in my ignorance - tried a sun shot - NOT TO BE. (Warning - false horizon no use when sun overhead!!!!)

    But all this was part of the very steep and hot learning curve - and to add to my woes my wife kept saying - does it work - (not having the faintest idea (like most people of astro-nav)) - sweat pouring down me - and by now the glasses over the false horizon completely fogged up with condensation - not withstanding the glass table reflecting a 2nd image of the sun at me - and the cat sitting on the table wanting a pat - and in my ignorance making the false horizon shimmer and tremble - which was opaque anyway.

    I gave up - put the sextant away - and went to get some hardware at the local huge Bunnings!!!! - Nah I said to my wife it doesn't bloody work!!!!

    1600 local time for another go - false horizon still on table - almost boiling in the hot sun - time to rethink things.

    Lucky section is elongated E-W so sun disappears down the back but is visible until about 1800.

    Cat has disappeared - place towel under false horizon - wipe glass on false horizon but only put 1 in place not 2 - the up breeze one - sun is in a better position. play around - almost blind myself trying to find the sun - as filters make it difficult to differentiate between false and true image - ..... place towel under false horizon to stop glare from glass on table.

    And now it is 1700 - and sun obscured by big confer branch.

    Move false horizon to ground - no more shimmer - hmm - position - sit on chair - ah now things are working - sun disappears - damm - large sun umbrella obscuring true image - reposition - not much time left.

    And finally - all the GODS decide to give me a break - 1702 - 2 images - aligned - my 1st reading. No pen and paper - oh well - get carpenters pencil and block of wood - 1703 - voila!!!!!!!!!! my 1st shot.

    Didn't compute it - just wanted to take it.

    You beauty -  Bob I need that aero-sextant ASAP !!!!!!

    Regards Howard G

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