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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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