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From: Courtney Thomas (no email)
Date: Fri Jun 10 2005 - 17:32:56 EDT
Assuming the inverting scope of the -SNO-M to be like the SNO-T:
Would the 8 screws on the barrel mount bracket, nearer the end opposite
the eyepiece...be the collimation adjustment on the SNO-M ?
Or only 4 of them ? If yes, which 4, the most or least, forward ?
If yes, do you know the proper adjustment sequence ?
Thanks again,
Courtney
On Fri, 2005-06-10 at 15:01, Alexandre Eremenko wrote:
> 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
> http://www.maurnavy.com/index.html
> Picture 2 shows an SNO-M with inverting scope (which has collimation
> adjustment).
> 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
> > > >
> >
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