Next message: Robert Gainer: "Re: Plastic sextants and prejudice. was: GPS shortcomings."
On Fri, 10 Jun 2005, Bill wrote:
> > Once Bill suggested to adjust collimation error
> > with a hammer...
>
> For the record, the suggestion was tongue-in-cheek.
But speaking seriously, just HOW do you adjust collimation
error? Fred told me (off the list) that one can try to grind
the fork carefully.
I understand that when the frame and scope are made on
the same factory and sold together, the collimation error
is supposed to be zero, and the fork is supposed to be rigid
enough, so that the error never appears.
But if you buy an additional or replacement
scope from another source...
the risk is probably substantial.
Alex.
P.S. Returning to the e-bay picture... you will probably have a nice
view of the horizon with this sextant... unobscured by the
mirrors and filters, so it can be used as a binocular:-)
A careful look at the fork suggests that the telescope could be
just an ordinary monocular (not a real sextant telescope) which
someone tried to attach to the sextant but did it very crudely.
