Hamma
Member
A much more elegant solution than the one I just posted.
I blame Wine Time and a lack of empathy for arithmetic.
UTC / Am I being thick?
- Thread starter Hamma
- Start date
A much more elegant solution than the one I just posted.
I blame Wine Time and a lack of empathy for arithmetic.
Conachair
Guest
Sandy
Well-known member
+1
ithet
Well-known member
Time and Time Zones
Confusion here with TIME ZONES i.e. UT, UT-1, UT-2, UT+1 etc. and local Standard TIME.
Thus in UT-1 local Standard time is UTC+1!
Also UTC is a reference TIME, and is of course, the same anywhere in the world.
The Time Zone does, rather confusingly, have a negative value for those places that set their standard ahead of UTC. This is because at such places the local noon (say) occurs before noon in Time Zone UT(0), and thus before UTC reaches that time value. I.e for France (UT-1) 1200 French Standard Time occurs at UTC 1100. So the convention is -ve because they get to any particular local time of day sooner!
In the almanacs tide tables are usually given in the local Standard Time. Therefore you need to apply the correction given (e.g. for France -1 hour) to relate them to UT (if you are reading a clock set UTC). Of course if reading from a lock set to BST you would also have to add the (UK) hour difference on (so for France there would be no corection in summer - to get to French Standard Time).
Of course, if you are in say France then you could just work on the local time and not need to make any correction except to add the 1hr if it is French Summer Time.
The aviation world is slightly different, in that everything is related directly to UTC and these currections for local Time Zones are not normally officially used.
Confusion here with TIME ZONES i.e. UT, UT-1, UT-2, UT+1 etc. and local Standard TIME.
Thus in UT-1 local Standard time is UTC+1!
Also UTC is a reference TIME, and is of course, the same anywhere in the world.
The Time Zone does, rather confusingly, have a negative value for those places that set their standard ahead of UTC. This is because at such places the local noon (say) occurs before noon in Time Zone UT(0), and thus before UTC reaches that time value. I.e for France (UT-1) 1200 French Standard Time occurs at UTC 1100. So the convention is -ve because they get to any particular local time of day sooner!
In the almanacs tide tables are usually given in the local Standard Time. Therefore you need to apply the correction given (e.g. for France -1 hour) to relate them to UT (if you are reading a clock set UTC). Of course if reading from a lock set to BST you would also have to add the (UK) hour difference on (so for France there would be no corection in summer - to get to French Standard Time).
Of course, if you are in say France then you could just work on the local time and not need to make any correction except to add the 1hr if it is French Summer Time.
The aviation world is slightly different, in that everything is related directly to UTC and these currections for local Time Zones are not normally officially used.
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