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: C.Plath on Ebay
    From: Alexandre Eremenko
    Date: 2005 Jun 10, 15:01 -0500

    In Russian sextants, collimation adjustment is
    not a feature of the sextant, but a feature of the scope.
    I have never seen an SNO-M in real life, but from the pictures
    I conclude that they come with two kinds of scopes.
    (Like SNO-T). It is the UNIQUE Russian INVERTING SCOPE
    which has the collimation adjustment.
    I have not seen ANY other scope like that, and I wonder why
    all Call Nav books still mention this adjustment
    (which cannot be made on anything but this Russian inverting scope).
    All kinds of Russian sextants and scopes that I know can be seen in
    Picture 2 shows an SNO-M with inverting scope (which has collimation
    Picture 1 shows an SNO-T but with ordinary (straight) scope.
    (New SNO-T come with two scopes: ordinary and inverting)
    Picture 4 shows some old sextant resembling SNO-M with
    some old scope (possibly inverting)
    which also has the collimation adjustment,
    but this is not the modern inverting scope.
    On Fri, 10 Jun 2005, Courtney Thomas wrote:
    > Then the SNO-M does not have the collimation error adjustment ?
    > Thank you,
    > C.Thomas
    > On Fri, 2005-06-10 at 02:05, Alexandre Eremenko wrote:
    > > Yes, of course.
    > > This picture could be used in a beginner's
    > > textbook to explain what is "collimation error":-)
    > > Modern sextant scopes (for the reasons that excape me)
    > > do not have collimation error adjustment,
    > > with one exception: the inverting scope of SNO-T.
    > > Once Bill suggested to adjust collimation error
    > > with a hammer...
    > >
    > > This is apparently what the owner of this sextant did,
    > > and after he failed, he sells the sextant:-)
    > >
    > > Alex.
    > >
    > > On Thu, 9 Jun 2005, Robert Eno wrote:
    > >
    > > > Have a look at this sextant on e-bay.
    > > >
    > > > Are my eyes deceiving me or is the rising piece on the scope bent out of shape?
    > > >
    > > > http://cgi.ebay.ca/ws/eBayISAPI.dll?ViewItem&category=37971&item=7328115519&rd=1
    > > >

    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