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I have used this book extensively and find a number of shortcomings.

The table lookup process is error prone and slow due to top/bottom access to 
the tables, the unnecessary combination of the Lat Dec with the sum res table 
and the total absence of any indexing mechanism. I have resolved this by 
recreating and reprinting the tables. I use a separate Lat Dec Table, 6 pages 
tab indexed by degrees a double facing page covering 30 degrees. The sum res 
table is extended to 12 pages each double page covering 15 degrees and is tab 
indexed by degree sum and res making getting to the right page instantly a 
snap. The remaining 6 pages cover LHA 90 to 180 indexed by degrees. All of 
these are double facing pages giving the maximum coverage on one opening. I 
have eliminated bottom access with two additional computation steps, if LHA 
is greater than 180 then tableLHA=359.60-LHA and by finaly extracting Z from 
the top of the res table alt=89.60-Z. Despite the additional steps I have 
found this is MUCH faster and less stressful to use despite an extra 4 pages 
of tables.

As has been already discussed the inclusion of several different methods of 
azimuth determination is confusing to the novice. My personal preference is 
for Weir diagrams. The result is unambiguous and can be transfered directly 
from diagram to plotting sheet using a Bretton plotter. The diagrams provide 
in the book are not big enough or detailed enough although the idea of 
splitting them into four separate diagrams is a good one. 

Despite these problems the book is a good minimalist solution to get you home 
astronav. It could be much improved by the suggestions above even if we had 
to cut out the tabs ourselves. Please International Marine for the 2011-2015 
edition.


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