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
    S.I.R.S. sextant calibration sheet
    From: Andreas Gwilt
    Date: 2022 Jul 28, 12:08 -0700

    Hello all,

    this is my first time actually writing anything after almost a year of lurking -- I have a lovely Admiralty Patt 491 sextant with a rather overwhelming calibration sheet issued by S.I.R.S. Navigation Ltd. in 2004, the summary of which is in the attachment. I'll just list all my questions:

    1. Am I right in thinking that Error is the number to look at, and Diff. is probably just the difference to the (nonexistent) previous calibration sheet?

    2. If so, do I want to add or subtract the Error values from my reading?

    3. Does the Tol: +- 72" really mean a tolerance of over a minute for that measurement, in which case isn't the whole thing rather useless?

    Andreas Gwilt

    File:


       
    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