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: Longhand Sight Reduction
    From: Peter Monta
    Date: 2014 Jul 29, 14:37 -0700
    Hi Francis,

    I may have a look at a quick prototype using your current scales, re-sized to slightly larger tubes. You mentioned some inaccuracies in the current scales. Could you elaborate so I know what to expect?

    Here is some analysis of the accuracy of the original scales:
    Of course the new scales should be perfect, since they were computed purely in software.   The printer might introduce some small errors if it's not perfectly linear in its x axis (linearity in the y axis doesn't matter).  Inkjets might do better than laser printers.

    I should be able to re-size your PDF versions ok. I can then put the re-sized mini Fuller sin/cos scale on in place of the Otis King  current log scale and see if it works.

    Are you happy with me using your scales like this, experimentally?

    Sure, no problem at all.  For an even quicker prototype, you can assemble a paper Otis King directly from the single sheet of paper and some tape---I've found it works pretty well.

    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