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
    Name or NavList Code:
    Email:
       
    Reply
    Re: Geometry of SNO-T
    From: Alexandre Eremenko
    Date: 2004 Oct 14, 12:36 -0500

    Herbert:
    
    On Thu, 14 Oct 2004, Herbert Prinz wrote:
    
    > How do your visors work? Can you clamp them on?
    
    They are L-shaped pieces of aluminium, about 1 inch high,
    1/2 inch wide with sharp upper edge.
    They cannot be clamped. You just put them on the arc.
    
    Using these visors, it is hard to keep your eye precisely
    on the height of the visors upper edges. So I think the
    cylinders would be better (their flat tops would help in control
    your eye position).
    That's why I proposed a modified version of the test using these visors:
    they should be installed on unequal distance from the axis,
    to compensate the excentricity of the mirror.
    This distance is easy to find experimentally, in my case it is
    about 5 mm.
    And the criterion that they are installed correctly is this:
    
    the alignment that you see during the test does not depend on your
    eye position:-)
    
    There is only one position of the visors with this property.
    (Assuming their centers near 0d and 120d and the index is installed
    on 35 d).
    
    Alex.
    
    
    

       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Get a NavList ID Code

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    A NavList ID Code guarantees your identity in NavList posts and allows faster posting of messages.

    Retrieve a NavList ID Code

    Enter the email address associated with your NavList messages. Your NavList code will be emailed to you immediately.
    Email:

    Email Settings

    NavList ID 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