Welcome to the NavList Message Boards.


A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Add Images & Files
    Re: NOW what?
    From: Robert Wyatt
    Date: 2015 Aug 19, 14:23 -0500

    The accuracy of Google Maps has been consistently tweaked by their staff
    since it rolled out some years ago. The corrections have been somewhat
    aided by 3-D projection of the imagery over terrain models (where you
    might see a "waterfall" that looks like a "river" if they are not
    aligned correctly) and also significantly improved by user reports and
    other projects such as OpenStreetMap.org.
    I would expect you to find some areas which are significantly (an order
    of magnitude) more accurate than other less-frequented areas.
    David Pike wrote:
    > One thing this discussion shows is how remarkably accurate the lat and long 
    readout on Google maps, which is presumably tied to WGS84, can be.  If you 
    look for ‘Greenwich Park London’ and then go to Earth and go to maximum 
    enlargement, you can actually see the stainless steel Prime Meridian line.  
    Place the marker over it and select left click.  You’ll get 51,477881, 
    -0.001502.  Multiply that by 3600 and you’ll get a longitude of 5.41”W.  
    Thrilled by this I thought I’d enter the figures I posted earlier in the 
    week.  The marker comes about a yard away from the little white table I sat 
    my GPS on, which shows my GPS was considerably more accurate at that instant 
    than the figure it was suggesting.  You’re correct Gary.  You can see where I 
    live.  What’s it like in other parts of the World?  Dave

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.

    Email Settings

    Posting Code:

    Custom Index

    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site