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  #1  
Old 06-11-09, 19:37
AOWYN AOWYN is offline
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Default Astro reduction forms

Does anybody have any decent sun sight reduction forms giving a simple layout.

I know that any piece of paper can be used for the basic arithmetic, but I am more likely to be consistent if I print a nice pile of neat and tidy forms.
As there are many experienced navigators out there I thought it worth asking for a copy of somebody else's preferred layout before I did gout my old books to make my own.

Thanks in advance
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Old 06-11-09, 20:14
alant alant is offline
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Originally Posted by AOWYN View Post
Does anybody have any decent sun sight reduction forms giving a simple layout.

I know that any piece of paper can be used for the basic arithmetic, but I am more likely to be consistent if I print a nice pile of neat and tidy forms.
As there are many experienced navigators out there I thought it worth asking for a copy of somebody else's preferred layout before I did gout my old books to make my own.

Thanks in advance
You can get them in pad form from Kelvin Hughes/Bookharbour.com
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Old 06-11-09, 20:23
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sarabande sarabande is offline
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fairly standard forms available here

http://www.cockpitcards.co.uk/userimages/procart4.htm


but many examples in correspondence course paperwork too, e.g. Chichester, RYA.


Also one in a .pdf which is not a model of clarity, but is thorough
http://www.eej.ulst.ac.uk/~ian/astro...n_Proforma.pdf
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Last edited by sarabande; 06-11-09 at 20:26.
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  #4  
Old 06-11-09, 20:28
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snowleopard snowleopard is offline
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Originally Posted by alant View Post
You can get them in pad form from Kelvin Hughes/Bookharbour.com
The problem with most commercially available forms is that they add unnecessary complications. Most of us only sail in summer in the northern hemisphere so we don't need to allow for southerly declination or south latitude.
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Old 06-11-09, 20:39
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LadyInBed LadyInBed is offline
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http://www.irbs.com/bowditch/pdf/chapt20.pdf
page 310

You can download the whole manual 38 chapters plus glossaries from
http://www.irbs.com/bowditch/
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  #6  
Old 06-11-09, 21:31
sticky sticky is offline
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Default Astro Navigation sight reduction forms

If you would like to send me your email address, I will send you the forms I have devised. Mk l is for those who are pretty proficient in the game, Mk ll is for those who have a bit of creeping senility and tend to forget the process.

Sticky
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  #7  
Old 06-11-09, 22:34
JayBee JayBee is online now
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Smile Astro Nav (Sight Reduction Forms)

There are dozens of different sight reduction methods - ranging from the cosine-haversine formula with 5 figure logs to Sight Reduction tables for Air Navigation (AP 3270, HO 249) and everything in between. Each of them requires a different form. Even sextant altitude corrections and azimuth calculations have different methodology, so there isn't one good form for general use.

Probably best to become familiar with your preferred method first, understand what you are doing, then design your own form or adapt someone else's.

Good luck!
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Old 07-11-09, 14:26
timbartlett timbartlett is offline
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I use the ones that come in ring bound pads from Staples or Rymans.
They say things like "Shorthand Notebook" on the front, and I find them incredibly versatile! :-)
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Old 07-11-09, 19:23
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davierobb davierobb is offline
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pm me your email add and I'll send you some I created earlier.... Also have a crude excel sheet which does calcs for you, you still need to get all the data from tables. The sheet was good enough to find eror in Tom Cun...... book.
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  #10  
Old 07-11-09, 20:02
BelleSerene BelleSerene is online now
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Default My graphical Astro proformas

When I was teaching myself Astro, I created these graphical proformas. I attach them in case they're of use to anyone else.

They're complete with schematic geometry as an aide memoire.

I'd value thoughts from anyone on these.
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