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Re: SNO-T Sextant
From: Courtney Thomas
Date: 2004 Aug 11, 09:43 -0500
From: Courtney Thomas
Date: 2004 Aug 11, 09:43 -0500
Thank you for the information Bruce. I have a SNO-M sextant [same as a SNO-T, I think] that has only the inverting scope and have not tried to use it and was thinking of getting the shorter scope. But, it sounds like maybe I don't need to. Pardon my obtuseness, but what is a "rough contact" regarding connecting scope to frame, please ? Also, why do I need it ? Appreciativley, Courtney Bruce Stark wrote: > Courtney, > > I wanted an inverting scope partly because the old-timers used them, and > because it was Lewis's favorite (Lewis as in Lewis & Clark). I also > wanted to be able to measure long lunar distances accurately. An > inverting scope has wires in the field of view that help you keep the > plane of observation parallel to the plane of the instrument. On page > viii of the introduction to my Tables there's a small table showing how > important this can be. You'll find similar tables in Bowditch, Raper, > and other old manuals. > > What threw me off in using the scope was that, with everything inverted, > normal reactions had the opposite effect of what was wanted. How would > you like to drive through town with a car in which the gear shift was > upside-down and backward, and that went left when you turned the wheel > to the right? > > Learning to use an inverting scope is rather like learning to ride a > bicycle. Don't frustrate yourself by working too hard at it. Just give > it a try now and then until you get the hang of it and it becomes > "instinctive." > > Also, be sure to get a rough contact before putting the scope on the > sextant. > > Bruce > -- s/v Mutiny Rhodes Bounty II lying Oriental, NC WDB5619