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Index error adjustment...
From: Russell Sher
Date: 1999 Jan 26, 09:25 EST
From: Russell Sher
Date: 1999 Jan 26, 09:25 EST
Hi - With all the talk on sextants, perhaps I can squeeze in a question about index error adjustment; I have an instrument which has two right-angle shaped brackets for assisting with index glass adjustment - With the instrument held horizontally, these calibrating brackets are placed on the arc so that both the reflected and true images are seen. The relative heights of these are adjusted into co-incidence with the adjusting screw to give perpendicularity. When I removed these brackets and eye-balled the arc directly, after performing the adjustment, I noticed that there was still some error - In other words, these two methods are possibly not as reliable as each other- OR is this a case of parallax error, or the way which I am viewing the arc? Celestaire (www.celestaire.com) market calibrating cylinders for the same purpose - does anyone have any experience with these? Any comments etc. regards Russell =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-= =-= TO UNSUBSCRIBE, send this message to majordomo@XXX.XXX: =-= =-= navigation =-= =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-=