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Re: Reducing back sights
From: Henry Halboth
Date: 2004 Aug 10, 14:44 -0400
From: Henry Halboth
Date: 2004 Aug 10, 14:44 -0400
Although Bowditch explains it somewhat differently, I believe you have it right. Bowditch subtracts the raw back sight from 180-degrees, then reverses the sign of the IC and Dip, which amounts to the same thing - just be careful as to when you subtract from 180-degrees. On Tue, 10 Aug 2004 07:50:17 -0300 Jim Thompsonwrites: > Neither Dutton's nor Bowditch explain back sight reduction in > sufficient > detail for me to be confident about the process. My understanding > is this: > > 1. Raw altitude = back sight. > 2. Corrected raw altitude: apply Index Correction and dip. > 3. Corrected hs = 180d minus corrected raw altitude. > 4. Then reduce the corrected hs as usual. > > True, or bungled? > > Jim Thompson > jim2@jimthompson.net > www.jimthompson.net > Outgoing mail scanned by Norton Antivirus > ----------------------------------------- >