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Re: Correction vs. error
From: Martin Caminos
Date: 2024 Sep 25, 22:00 -0700
From: Martin Caminos
Date: 2024 Sep 25, 22:00 -0700
Hello Paul, thanks for your message.
The sextant measured distance was 0.1' higher than the calculated distance from the almanac (21° 39.1' vs 21° 39.0').
In other words, the index error is 0.1' within the arc, so it has to be deducted from the Hs to obtain Ha. That is why in this case, the index correction is negative.
We can still use the formula Ha = Hs +I -D, but it this case I is a negative number and D is zero.
Ha: 21° 39.1 +(-0.1') - 0' = 21° 39.0'
As usual, all comments and suggestions are welcome.
Thanks, Martin
