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
    Name or NavList Code:
    Email:
       
    Reply
    Re: Reliable Index Correction to a Tenth Minute of Arc
    From: Brad Morris
    Date: 2010 Feb 22, 09:10 -0500

    Hi Bill

     

    Setting the optical path of any instrument takes care and patience.  When we combine that optical path with rotary motion, many factors apply, including as you note, stick slip, vernier interpretation and prismatic effects.

     

    Perhaps I theorize, the oft told instability of the index error is nothing more than the user’s ability to make the measurement!  So we chase what we think are instrument errors but really, at least in my case, are mark 1 eyeball errors.  Perhaps, should I have had thousands of observations under my belt, like Chief Franklin or Henry, I could do a bit better. 

     

    I will withhold congratulations, as I believe the stated terms were 30 measurements with the IE known and the standard deviation zero.  None the less, I do know which instrument I would use, should I have access to your storehouse of sextants! J 

     

    Best Regards

    Brad

     

     

     



    "Confidentiality and Privilege Notice
    The information transmitted by this electronic mail (and any attachments) is being sent by or on behalf of Tactronics; it is intended for the exclusive use of the addressee named above and may constitute information that is privileged or confidential or otherwise legally exempt from disclosure. If you are not the addressee or an employee or agent responsible for delivering this message to same, you are not authorized to retain, read, copy or disseminate this electronic mail (or any attachments) or any part thereof. If you have received this electronic mail (and any attachments) in error, please call us immediately and send written confirmation that same has been deleted from your system. Thank you."
       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Get a NavList ID Code

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

    A NavList ID Code guarantees your identity in NavList posts and allows faster posting of messages.

    Retrieve a NavList ID Code

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

    Email Settings

    NavList ID 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