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    FW: Polaris isn't so easy!
    From: Doug Royer
    Date: 2004 Apr 6, 11:33 -0700

    -----Original Message-----
    From: Royer, Doug
    Sent: Tuesday, April 06, 2004 10:07
    To: 'jim2{at}JIMTHOMPSON.NET'
    Subject: RE: Polaris isn't so easy!
    
    
    
    
    
    1. Polaris is dim enough that it has to be shot later in twilight, reducing
    the window of opportunity because the horizon is worsening rapidly then,
    even as Polaris is becoming brighter.
    2. An artificial horizon (pan of oil) can work, with practice, but it is not
    easy to use initially.
    Yes
    3. Optimize environmental factors:
    3a. Pick a spot with minimal urban light pollution.  (I was standing beside
    a lighthouse!!).
    Very important.Also atmospheric clarity(absence of haze etc)is important.The
    best results I've had were taken in the desert.No urban light pollution and
    chrystal clear atmosphere.
    3b. Dark adapt eyes carefully, and keep them dark adapted (red flashlight).
    Very important!
    3c. Use AH when there is no wind.
    Use an AH that has a cover or shield if liquid is used.I've used a relective
    hard surface in the past.
    4. Use a telescope. The 2.5 power will work, but higher power is better,
    though not necessary.
    Indeed.But be advised other problems then arrise with useing a higher power
    scope.
    5. Use a split horizon rather than whole horizon.
    Most assuredly!!!!!!
    6. Preset the sextant for predicted altitude, or reverse the sextant.  I
    have been trying to bring Polaris down to the horizon, which is my usual
    practice with bodies.  I was losing it about a third of the way to the
    horizon.
    Good procedure to follow.
    7. Polaris is easy to find at our latitude because it is the first star to
    appear at 45 degrees due north and is "all alone" for a while, until its
    neighbours appear.  But the neighbours are easy pointers anyway.
    You bet.
    8. Practice, practice, practice.  With time shooting Polaris will seem easy,
    but not the first night out, or even the second.
    Again,you bet.
    
    
    

       
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