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
    Calibrating a Bris sextant
    From: Marty Lyons
    Date: 2017 Aug 13, 09:31 -0700

    I find myself confused. I am trying to make a calibration chart. I take the Bris to a shoreline and sight the center of the sun touching the horizon and record the time. Using software, I look up the Hc of the sun for this time and location. In the case of the center sun shot, this Hc is the angle that the Bris read at that time. No problem yet. 

    Now, I try a an UL shot, ( actually occurs before the center shot because sun is rising in morning), and record the time. I look up Hc for the sun at this time, which is the center of the body.  Do I add semidiamter to Hc or subtract to get the angle that the Bris measured? 

    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