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    Re: No Celestial Love in ECDIS
    From: Greg Rudzinski
    Date: 2018 Mar 11, 16:09 -0700


    A time sight longitude by formula (or Morelli tables) is good enough if meridian angles are greater than 30°.  Not too hard to do by trig calculator and of course no azimuth to worry about but requires a reasonably good DR knowledge of latitude. Ex-meridians are generally good for meridian angles less than 10°. Combine the time sight and ex-meridian for a fix with no need for a plot.  Old school though.

    Greg Rudzinski 


    From: Jeremy C
    Date: 2018 Mar 11, 15:23 -0700

    I think you may be onto something Greg, although much slower than an integrated machine.  Using calculators/software with the DR as the AP, and making a Mariner's Marker on that point and then a series of range and bearings for each body.

    I seem to remember Longitude by Chromometer/Time sights were fairly limited by the body needing to be bearing nearly E/W no?  It's been a long time since I've done one.

    In any case, I will see if I can give feedback to the company.  I don't know if I'll be able to experiment for awhile however.


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