Corrupted HP table

[pabrides]

[quote pid='574' dateline='1531367588']
OK, Ed, I stand corrected !!!  The second HP table is NOT errant.

I chewed on a sample moon shot and found both table answers exactly the same... Its curious that I havent seen the second table instructions... That table adds some excitement to the reduction process... The more steps there are the more opportunity for errors - so when a reduction works out ok one feels great that all that hard work lead to something fairly accurate.  However, to be clear, using the second HP table, the one without UL and LL division, the UL -30 correction is of no use?

thanks
Joe

Joe,

What UL -30 are you referring to?  'Don't know where that is.

Are you referring to the UL subtraction of SD (semi-diameter)?

Ed
[/quote]


Ed, this should make it clear; here is an excerpt from Bowditch.. Note second paragraph.

"Horizontal Parallax Correction: This correction is unique
to reducing Moon sights. Obtain the H.P. correction value from
the daily pages of the Almanac. Enter the H.P correction table at
the back of the Almanac with this value. The H.P correction is a
function of the limb of the Moon used (upper or lower), the ap
parent altitude, and the H.P. correction factor. The H.P.
correction is always added to the apparent altitude.
Moon Upper Limb Correction: Enter -30' for this
correction if the sight was of the upper limb of the Moon.
Correction to Apparent Altitude: Sum the altitude
correction, ... , ... , the horizontal parallax correction, and the
Moon’s upper limb correction. Be careful to determine and carry
the algebraic sign of the corrections and their sum correctly.
Enter this sum as the correction to the apparent altitude.
Observed Altitude: Apply the Correction to Apparent
Altitude algebraically to the apparent altitude. The result is the
observed altitude."

And here is the example they give:

"> Body Moon (UL)
Index Correction 0.0'
Dip (18 feet) -4.1'
Sum -4.1'
Sextant Altitude (hs) 26° 06.7'
Apparent Altitude (ha) 26° 02.6'
Altitude Correction +60.5'
Additional Correction 0.0'
Horizontal Parallax (58.4) +4.0'
Moon Upper Limb Correction -30.0'
Correction to ha +34.5'
Observed Altitude (ho) 26° 37.1'

Also the instructions with the first Moon correction table refers to the -30 upper limb correction.
joe