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Re: Geometry of SNO-T
From: Alexandre Eremenko
Date: 2004 Oct 14, 11:25 -0500
From: Alexandre Eremenko
Date: 2004 Oct 14, 11:25 -0500
Bill: On Wed, 13 Oct 2004, Bill wrote: > I had posted a question a while back, and have received no response. Since > Alex seems to have a good grasp of this now, I will ask him and others to > address it. > > "If the front-silvered mirror is no longer on the axis of the rotation, will > this affect the sextant's performance?" On my opinion, the answer is no. As I said before, this is irrelevant for the sextant performance (but relevant for perpendicularity test/adjustment). Let people correct me if I am missing something here. In SNO-T the distance from this plane to this axis is about 6mm (which is my crude extimate, I was afraid touching the mirror while measuring). I have no clue why they designed it like this. It seems they did it intentionally, and they knew the adjustment will be trickier, that's why they supplied the visors as standard accessories. The closest to SNO-T Western sextant is Freiberger. Question to Freiberger owners: does it also have this feature? Alex.