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Apparent altitude correction when using artificial horizon
From: Peter Mackenzie
Date: 2025 Jan 22, 05:35 -0800
From: Peter Mackenzie
Date: 2025 Jan 22, 05:35 -0800
hi
i am struggling to work out what the altitude correction should be to a sextant reading when using an artificial horizon when performing a noon sight? (in my case a tray of water). Using the Nautical almanac, do you take half the difference between the LL and UL correctoins? EG: if the apparent altitude is, say, 15º 10', and the LL correctoin is +12.8 and the UL is -19.5, do you take -6.7 as the correction?
any suggeston welcome
Peter