Celestial Navigation

[hoppy1848]

I want to teach myself as best I can, Celestial Navigation. To this end I have bought Tom Cunliffe's 'Celestial Navigation'. In the book Tom comments that 'some of the cheap plastic one's work very well'. I am tempted to buy one of the ex German Democratic Republic's sextants which regularly appear on Ebay and seem to go for circa £300. On the other hand for purposes of learning and at least gaining a basic proficiency I'm tempted to buy 'plastic' if Tom's judgement is correct. It seems to me that if I can get basic proficiency then that would be the time to purchase a more robust piece of kit.

Can you advise re the use of a plastic sextant- do you agree with Tom or would you just jump in a buy a robust piece of kit?

Thanks

 

[Reverend Ludd]

The Davis Mk15 is ok but the Mk25 is better.
For £300 you will find something quite a bit better though.
Maybe a Frieberger.

Here is a good little site thats worth a look.

http://celestial-navigation-course.com/

 

[hoppy1848]

Captain, many thanks. It is a 'Freiberger' that I've seen on ebay.

The link looks terrific to.

 

[Lady Campanula]

You'll likely get your money back, whatever you choose to do, unless you manage to damage what you buy.

I'd encourage you to get a cheap plastic job, for you're more likely to be at ease handling it and learning how to look after it.

 

[helixkimara]

nav

Just be aware that at times of conflict in sensitive area's the Americans have been known to move the sun and relevant celestial bodies to confuse possible hostile navigation.

 

[Skylark]

Even the cheap-and-cheerful Ebbco will give you a reasonable sun sight, in my experience. I used one on a south-bound passage and was quite surprised to witness the index error increase day by day with increasing ambient temperature. Not a problem, merely an observation.

Good quality optics come into their own when you're chasing those impossible to find dots in the twilight sky!

As others have said, there always seems to be brisk trade of sextants on e-bay. Obviously avoiding the ornamental versions, I'm sure you can trade-on anything you buy without loosing your shirt. To own a high quality instrument is a joy (if you are so inclinded).

I did the RYA course but didn't use a sextant in anger for a couple of years, hence forgot most of it. I bought Tom's book. I'm a big fan of Tom but only found his book useful as a revision aid. Granted we're all different as are our learning processes. I liked the Adlard Coles Ocean Yachtmaster as it gave more detail. The Mary Blewit one is often referred to. I would regard it as an abstract of Tom's.

If you're a recreational sailor, rather than a trained military or commercial navigator, there is much satisfaction and reward in the long-hand sight reduction process (it ain't rocket science) and plotting a position line (that passes through your gps track).

Good luck.

 

[Delfin]

I want to teach myself as best I can, Celestial Navigation. To this end I have bought Tom Cunliffe's 'Celestial Navigation'. In the book Tom comments that 'some of the cheap plastic one's work very well'. I am tempted to buy one of the ex German Democratic Republic's sextants which regularly appear on Ebay and seem to go for circa £300. On the other hand for purposes of learning and at least gaining a basic proficiency I'm tempted to buy 'plastic' if Tom's judgement is correct. It seems to me that if I can get basic proficiency then that would be the time to purchase a more robust piece of kit.

Can you advise re the use of a plastic sextant- do you agree with Tom or would you just jump in a buy a robust piece of kit?

Thanks

You need not spend that much on a quality sextant. I used an Astrid and found it very accurate, but you can buy a high quality German C Plath for less than 150 pounds. http://cgi.ebay.com/C-PLATH-Marine-...960?pt=LH_DefaultDomain_0&hash=item3f0b1020a8

A plastic will work ok, but you would enjoy owning a nicer instrument. Find a celestial calculator and do star sights. That's all I ever used, as I had a Merlin calculator that made the reductions easy and it was always fun to learn to identify the stars.

 

[Myk]

This is an excellent guide to get you started

http://www.minitransat650.com/Sextant_Users_GuideV6.pdf