Which sight reduction tables

[Jonny A]

Hi everyone, I'm about to dive back into doing celestial navigation after a 25 year break, and am looking for some suggestions for sight reduction tables. I remember previously using a single volume, one of the ones for Air Navigation, which I always found very easy to use and covered a large range of latitudes. Now of course I can't remember which one it was, and there seem to be do many options!

All suggestions on this gratefully received.

 

[Andy Johnson]

Hi Jonny, I have recently loaded up the 2024 set of almanacs and tables on my web site Astro Nav from Home (courtesy of “thenauticalalmanac.com” and they are free for private / non commercial use). These are not the only way but are the usual ones for the chosen position method of sight reduction. Good luck, sure it will all come rushing back !!
Andy Johnson

 

[Baltika_no_9]

That's a very useful collection of material you've put together there Andy. I've used thenauticalalmanac.com website for years and it is excellent.

On the OP's specific question on sight reduction tables, despite their being available in electronic form as you've provided I prefer AP3720 (Sight Reduction Tables for Air Navigation) or the NP303/Pub249/Ho249 equivalent in hard copy. They are often referred to as Rapid Sight Reduction Tables. One or both of V2 or V3 volumes depending on the latitude I'm sailing, V1 if planning on using stars. Entering the tables with Lat/LHA/Dec I find easier if the book is in front of me. That's just a personal preference though. The full set of three volumes does take up quite a bit of space.

 

[jdc]

I carry tables I created - the maths is pretty trivial after all - as when I first made them I couldn't afford the official 'air tables' but I could use the VAX at work to print things. I could just afford an Ebco Special sextant, so it was our sole means of navigation while doing an ocean race.

That was back in 1991, so time has moved on, but the same data, slightly better formatted I think, can be found at Awelina of Sweden Welcome Page under 'Sight reduction Tables downloadable files'. I still carry them on board. Also look at its associated 'ReadMe' an/or download the sight reduction app on the same site, which I update every year.

 

[Sandy]

Hi Jonny, I have recently loaded up the 2024 set of almanacs and tables on my web site Astro Nav from Home (courtesy of “thenauticalalmanac.com” and they are free for private / non commercial use). These are not the only way but are the usual ones for the chosen position method of sight reduction. Good luck, sure it will all come rushing back !!
Andy Johnson

Thanks @Andy Johnson loved the website and very quickly how to work out the historic sunrise/sunset times for a passage I crewed on a few years back.

 

[Andy Johnson]

On board I have the hard copies as well. I use the pdf versions at home to keep my practice up and I have loaded some of my practice examples up onto the web site on the worked examples page, taking my "sights" using the wonderful Stellarium app. I even wrote a book about it during lockdown ! Back end of last season I installed a NASA navtext and now have a dedicated tablet on the boat and have actually got to like using it for my astro nav as well, especially as I am still sitting in the marina for the time being. As the layouts are the same, there will be no issue switching back to the books if I forget to charge the tablet or it conks out !

 

[Porthandbuoy]

If you're only interested in working out Sun sights you could try my Almanac and Sight Reduction Tables. I developed them years ago when I was working offshore in the Med off Tunisa and GPS went screwy when the good ol' USA went to kick Saddam out of Kuwait.