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Many books also teach doing sight reduction using a pocket calculator.
It's WAY easier than HO229 and WAY more accurate than HO249.   So unless
  you want to eschew modern conveniences, I'd suggest first learning to
do reduction using a calculator and then learn the tables.  There's
enough to learn about getting from hs to Ho, Z to Zn, etc, not to have
to fight learning a tabular reduction method to boot.

I carry a solar-powered scientific calculator aboard my boat.  It cost
me all of $15 at K-Mart almost 15 years ago.  It claims that if there's
enough light to read the display, there's enough light to power it.  I
believe that -- I've used at night (but under normal cabin lights, not
red night lighting) and it's worked fine.

BTW, I also suggest using pre-printed sight reduction forms (they are
available for calculators and a number of the tables) rather than
scribbling everything down scattershot.  They help make sure you've done
everything needed.

Omitted from Doug Royer's note was mention of the Nautical Almanac Sight
Reduction technique (NASR);  if you have a copy of the Nautical Almanac
then you will automatically have the tables for doing sight reduction
using NASR.

Lu Abel



Royer, Doug wrote:
>
>
>
>
> For tables either H.O 249 or H.O. 229 or H.O. 214 are all very similar
> and 249 is the most convenient but only has a precision of one minute of
>
> arc which is an accuracy on one nautical mile which is realistic on a
> small boat. If you want higher precision, especially for practice shots
> while on shore, then 229 or 214 will do.  214 is out of print but I
> think its arrangements of the tables is more convenient than in 229.
>
> BTW, does anybody know why they switched from the 214 format to the 229
> format so you cant just do a round of sight using only one page as you
> could do with 214 but have to chase all over for the LHAs?
>
> My understanding for the change in format from HO-214 to HO-229 was for
> ease/speed of tabular reduction with about the same level of precision.
> That may be correct. HO-229 does eliminate a step or two compared with
> HO-214. But then kind of requires the addition of a step when computing
> the double 2nd difference.
>
> To expand on this further for the new guy's benefit:
> I, personally, like using the old HO-214.
> HO-249 vol. #1 is quick and easy to use but limits a person to using
> only the listed stars. Sometimes those listed stars can't be used
> because of local conditions but other, unlisted, bodies that may be
> useable can't be included for reduction because there is no data listed
> for them.
> HO-249 Vols. #2 and 3 are arranged in the same format as are HO-229 and
> does away with this limitation.
>
> If you want a short tabular method H.O. 208 is my preference.
>
> Good method. My preference is in using HO-211. It consists of 28 pages
> of data in one volume which covers it all from anywhere. Easy to use and
> quick for obtaining passable results with no limitations on which bodies
> may be used. For those minimalists in small vessels there is a 9 page
> volume of the same method.
> You can find many of these books on ebay.
>
> Or one may download a copy of both HO-208 and HO-211:
>
> http://www.geocities.com/sadams16/Navigation1.html
>
> Or the other methods if you desire. I just like having the hardback
> volumes of HO-214 thru HO-249 to use but it may not be practical in a
> small vessel or if money is an issue the above link will give you the
> volumes.
>
>
>
>
> >
>

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