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: Vernier explanation
    From: Peter Monta
    Date: 2022 Jun 27, 03:15 +0000
    Hi Don,


    Parallax in the camera view is not likely. The owner posted this inquiry specifically because he could not detect any difference in the spacing of the two scales by eye.

    Hmm.  Could the vernier have been mis-engraved, perhaps by configuring the dividing engine with settings intended for the arc?  How would that have gotten past final quality control?

    I'm tempted to do some analysis of the image, but that would have to estimate the camera pose and a good subset of the tick marks.  Four engraved circular arcs are also available as constraints.  Alternatively, could the owner supply a few more photos, for example with the camera directly above the vernier's 0, 2, 4, 6, 8, and 10 (using a fixed index-arm setting of course)?

    Cheers,
    Peter

       
    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