Expedition Navigation Software 
1 of 1- ZeeZee
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Offline - Registered: 3/30/2016
- Posts: 321
Magnetic or True?
Expedition can operate in Magnetic or True mode (Settings - Systems)
What do you use and why or when?
I personally tend to use True as that easily refers to what you see on the map,
- DuncanR
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- From: Up and down East Coast Aus
- Registered: 9/16/2015
- Posts: 471
Re: Magnetic or True?
Well, if no one else will jump in ....
I always use magnetic. Navigation is mostly about communication, and therefore talking numbers that steerers, trimmers and others can relate to when cold, wet and tired.And what they see on the dials is magnetic, so that's it. I have enough trouble having sensible conversations about COG vs Heading (both magnetic)!
Stay warm, dry, rational and focus on simple outputs.
Namaste
- Ernie M
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- Registered: 11/05/2015
- Posts: 419
Re: Magnetic or True?
I totally agree with Duncan, for the same reasons.
The only time I ever use True is in plotting celestial LOP's....pretty rare these days! The one exception is one East Coast U.S. race that gives a 3% TOT advantage for using celestial.
Cheers,
Ernie
- ZeeZee
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- Registered: 3/30/2016
- Posts: 321
Re: Magnetic or True?
Thanks for sharing.
Now the main compasses on deck are all electronic, why not just display all TRUE values on deck and use Exp in True mode? Intuitively this feels way simpler to me.
But as I never sailed in areas with a high variation, let alone made the transition between areas with different variation I have no experience here and I might very well miss something here!
- •
Thread Starter- Nick
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- Registered: 9/16/2015
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Re: Magnetic or True?
We've always used magnetic for the above reasons and most boats do use a magnetic compass. The original reason for the true option was in the southern ocean where the variation could exceed 40.
- Campbell_Field
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- From: UK
- Registered: 9/16/2015
- Posts: 238
Re: Magnetic or True?
I've never met a 'True' hand bearing compass...
:::Campbell Field::::::www.fieldyachting.com:::
- ZeeZee
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- Registered: 3/30/2016
- Posts: 321
Re: Magnetic or True?
That's 'true' Campbell ;-)
It would however be very easy and cheap to make with todays available sensors.
- •
Thread Starter- TomH
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- From: London (and Chichester)
- Registered: 2/06/2016
- Posts: 65
Re: Magnetic or True?
Surely that depends on deviation for the spot you're standing on to take the bearing? ;-) God, have I just made a deviation joke (hides in shame)...