Welcome to the NavList Message Boards.

NavList:

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

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    or...
       
    Reply
    Re: Distance Measurement - Tape vs Google
    From: Gary LaPook
    Date: 2013 Apr 11, 23:14 -0700
    The 15 foot value was just an estimate, no way to measure it. I just stood on the adjacent beach and looked at the side of the breakwater and estimated eye level and then used multiples of that to estimate the height of the breakwater.

    gl

    --- On Thu, 4/11/13, Brad Morris <bradley.r.morris---.com> wrote:

    From: Brad Morris <bradley.r.morris---.com>
    Subject: [NavList] Re: Distance Measurement - Tape vs Google
    To: garylapook---.net
    Date: Thursday, April 11, 2013, 8:32 PM


    http://fer3.com/arc/m2.aspx/Dipmeter-again-LaPook-apr-2012-g18850

    On Apr 11, 2013 11:26 PM, "Bruce J. Pennino" <bpennino.ce---net> wrote:

    Hi:
     
    My intent was to show everyone and myself that Google Maps Distance Calculator is just excellent for all distances starting at even 100 ft or 200 ft. The precision/accuracy increases so that at 500, 1000 ft or more vertical angular measurements achieve very reasonable precision with devices other than a theodolite.
     
    With a channel width of over 500 ft, I'm still curious to reconcile the HoE difference of 22.5 ft and 15 ft.  Which is the more correct value?  I believe that was in Gary's posting....but now I'm unsure of which message. Sorry, sometimes I lose track of the original message in a discussion..

    Bruce
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
    ----- Original Message -----
    Sent: Thursday, April 11, 2013 9:05 PM
    Subject: [NavList] Re: Distance Measurement - Tape vs Google


    Hi Bruce

    Gary LaPook wanted a very long baseline with the bubble sextant measured angle to improve the accuracy of his HoE, in his "Dip Meter Again" post. I think that's one of the reasons why he did it that way, using Google earth.

    You can use a lesser distance because of the greater angular precision of your theodolite. Hence the 200' restriction of your tape isn't a restriction! Nicely done.

    The bubble sextant, of course, cannot really compete with a theodolite for angular measure and thus HoE determination at a distance of 200'. Note that a larger population of bubble sextant owners are in the audience than theodolite owners. So for the benefit of those who have one and not the other, using a long baseline helps when determining HoE by bubble sextant.

    Brad


    ----------------------------------------------------------------
    NavList message boards and member settings: www.fer3.com/NavList
    Members may optionally receive posts by email.
    To cancel email delivery, send a message to NoMail[at]fer3.com
    ----------------------------------------------------------------

    View and reply to this message: http://fer3.com/arc/m2.aspx?i=123531

    View and reply to this message: http://fer3.com/arc/m2.aspx?i=123534

    View and reply to this message: http://fer3.com/arc/m2.aspx?i=123535

       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Join NavList

    Name:
    (please, no nicknames or handles)
    Email:
    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:

    Email Settings

    Posting Code:

    Custom Index

    Subject:
    Author:
    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