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: Metal versus plastic or better telescope?
    From: Alan S
    Date: 2012 Mar 27, 15:40 -0700

    Lu Abel:

    On the subject of accuracy, as memory serves, I once saw the following, NOT an exact quote, in a booklet describing the Plath sextant.

    Instrument Error was specified as no more than 12 seconds of arc, across the sextant arc, this was, as I recall, a guarantee. The commentary next went on to note, that on a small yatch, with sea running, the greatest error would come, not from the instrument, but from the operator, who might have great difficulty holding the horizon steady. It was suggested that the user concern himself with that aspect, rather than being overly concerned with "non adjustable instrument error"

    My Astra 111B's "qualification sheet" does not give corrections for various angles, as some I have seen do, rather it states, "This instrument is free of errors for practical use". While this might sound like "lawyers talk" I expect it is the truth. While the prices for Astras, newly purchased, have shown a significant increase in the last few years, they seem to be money well spent, looking at the costs of Plath and Tamaya sextants. By the way, is anyone other than the above mentioned making sextants these days, or have they become, like the slide rule, things of the past.
    Alan
    ----------------------------------------------------------------
    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
    ----------------------------------------------------------------

       
    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