French tide times

[shantih]

My north Biscay pilot states "tides in this area are based on UTC - 1. This means they are already adjusted to BST".
As BST is UTC + 1 is this a misprint, if not will someone please explain . . .

 

[Jungle Jim]

I predict this thread will start all sorts of arguments.

My instructor said 'now don't blame me but...' and then explained that UTC -1 means SUBTRACT 1 from the time to get back to UTC.
As an engineer it does my head in :ambivalence:

 

[shantih]

As an engineer it does my head in too Jim!! But also is an explanation that works
Thanks

 

[NealB]

As an engineer it does my head in too Jim!! But also is an explanation that works
Thanks

It's not just an explanation that works, it is exactly what it means.

Once you know that, it's not a problem.

Devised by a navigator, perhaps?

 

[capnsensible]

I predict this thread will start all sorts of arguments.

My instructor said 'now don't blame me but...' and then explained that UTC -1 means SUBTRACT 1 from the time to get back to UTC.
As an engineer it does my head in :ambivalence:

Dont engineers have datums?

UTC is it for marine navigators. The plus and minus tell you what to do to your clock to get it to UTC. It always wins.

 

[[70521]]

Dont engineers have datums?

Depends what type of engineer you are.

 

[Yngmar]

It's assbackwards in marine lingo for some reason. In computer lingo when we say UTC+1 we mean the time is in UTC plus one hour, so when it says 14:00 on there it means at 13:00 UTC. This makes much sense to me.

In marine lingo it's the other way around, at least most of the time, although I noticed several tide websites (like tides4fishing) do it the normal (above) way around, because sometimes sanity prevails in the end.

 

[capnsensible]

It's assbackwards in marine lingo for some reason. In computer lingo when we say UTC+1 we mean the time is in UTC plus one hour, so when it says 14:00 on there it means at 13:00 UTC. This makes much sense to me.

In marine lingo it's the other way around, at least most of the time, although I noticed several tide websites (like tides4fishing) do it the normal (above) way around, because sometimes sanity prevails in the end.

Of course, yeah I forgot, all those computer nerks around before the International Meridian Conference in 1884 didnt bother to turn up to tell them how it should really be done, the dozy time bandits.

 

[shantih]

Thanks to all

 

[davidej]

I predict this thread will start all sorts of arguments.

I partook in one of these a year or so ago.

It seems to me that nautical practice is exactly the opposite of what all the rest of mankind does and totally non-intuitive.

 

[ex-Gladys]

I partook in one of these a year or so ago.

It seems to me that nautical practice is exactly the opposite of what all the rest of mankind does and totally non-intuitive.

The marine description is that the TIMEZONE is UTC-1, which means that the clock time is UTC+1... It's an astro nav thing... In astro you need to know you Greenwich Hour Angle because the astro tables all relate back to that...

 

[capnsensible]

 

[shantih]

That's somewhat confusing, I thought I had it clear but maybe not. UT = GMT & UT + 1= BST. So does that mean clock time - 1 = UT or clock + 1 = UT?

 

[capnsensible]

UT is datum. Plus or minus tells you what to do to your clock to make it into UT.

Say you are in Antigua and you look at your watch. Right now it will read 0730. Time zone +4. Add that, gives you 1130 UT.

Because UK is in daylight saving, the clocks have gone forward an hour, so your UK watch will say 1230.

If you want your watch to be in UT, minus that hour to get it. UT -1.

Simply remember UT is the king. You adjust to it, It does not adjust to you.


I blame the world for spinning anticlockwise relative to the sun causing it to rise in the east and set in the west relative to your geographic position and the Greenwich datum. If only the Great Architect had spun it the other way, engineers and computer nerks wouldnt get so confused.......

Did you know that before clocks, witches called anticlockwise 'widdershins' ?

 

[capnsensible]

If Greenwich hadn't have got in before Paris, you might be suffering confusion caused by PMT......

 

[ithet]

My penny's worth:

The Almanac/pilot is telling you that the time zone is "UTC -1", i.e. the standard time there gets to (say) 12 noon an hour earlier than UTC.

The standard time for the zone is therefore equal to the sum UTC+1 (which is how most people/microsoft etc. think of it ).

Yes, its a daft standard.

 

[davidej]

Yes, its a daft standard.

Now we have sorted that out, we can argue about why SW winds come from the SW but SW currents flow to the SW.

Equally daft, but get over it -that's how it is

 

[capnsensible]

Yes, its a daft standard.

Why is it daft to adjust your clock to the datum?

 

[Sybarite]

My north Biscay pilot states "tides in this area are based on UTC - 1. This means they are already adjusted to BST".
As BST is UTC + 1 is this a misprint, if not will someone please explain . . .

Don't complicate life :

https://www.snsm.org/conseil/attent...MIsJbO9sOy1QIVm6ntCh0QAAMUEAAYASAAEgJrwfD_BwE