Question about GMT dive watches...

[Disastrous]

Which is, simply, how on earth do you use them as dive watches/timers if the bezel is marked for a 24 hour clock??

Surely it defeats the point of a dive watch, if it can't be used to easily calculate elapsed time? Or am I missing something...?

[trickywoo]

I don't think the 24 hour ring really stops you using it as a timer just makes it harder to read.

The vast majority of divers these days will use a computer anyway rather than a watch.

[Disastrous]

trickywoo said:

I don't think the 24 hour ring really stops you using it as a timer just makes it harder to read.

The vast majority of divers these days will use a computer anyway rather than a watch.

I know that but many would still use a watch as a backup. At least, I'd want my dive watch to be able to function as one!

Surely a gmt bezel would make no sense? How would you set it to countdown bottom time if the numbes bear no relation to the time? You'd be easier just not using the bezel surely, unless I'm missing how they work?

[trickywoo]

Disastrous said:

I know that but many would still use a watch as a backup. At least, I'd want my dive watch to be able to function as one!

Surely a gmt bezel would make no sense? How would you set it to countdown bottom time if the numbes bear no relation to the time? You'd be easier just not using the bezel surely, unless I'm missing how they work?

Furry muff. I guess the 'pointer' on the bezel would act as an aide-mémoire as to when the dive started.

[Disastrous]

trickywoo said:

Disastrous said:

I know that but many would still use a watch as a backup. At least, I'd want my dive watch to be able to function as one!

Surely a gmt bezel would make no sense? How would you set it to countdown bottom time if the numbes bear no relation to the time? You'd be easier just not using the bezel surely, unless I'm missing how they work?

Furry muff. I guess the 'pointer' on the bezel would act as an aide-mémoire as to when the dive started.

Aye, I see what you mean...just wondered if there was also a way of measuring 5 min increments like a standard bezel.

S'funny as I hardly ever 'need' a dive bezel, using it almost exclusively as a land based timer, and in fact a gmt bezel would be more use but I'd be bothered that it wasn't fit for purpose as a dive watch! Just 'in case'!

[Ikemi]

Alternatively, you could get a dive watch that displays GMT time on a dial, rather than hand/bezel combo ... Sorted! A bit like this Clerc Hydroscaph GMT, although the bezel on this isn't particularly easy to read, but you know what I mean ...

[Disastrous]

Indeed, and seems much more sensible to me.

What started this was looking at Steinhart watches and noticed they do one called the Ocean Vintage gmt, which whilst nice looking, seems somehow pointless as I can't see it as a die watch. Maybe if I tried to view it as a 'sailing watch' it'd make more sense

[marcosgt]

Ikemi said:

Alternatively, you could get a dive watch that displays GMT time on a dial, rather than hand/bezel combo ... Sorted! A bit like this Clerc Hydroscaph GMT, although the bezel on this isn't particularly easy to read, but you know what I mean ...

Today's master of understatement

M.

[CaptainSlow]

...or just get a uwatec dive timer as a backup to a computer. Dive watches are for the post dive debrief in the bar .... not underwater.

[Debaser]

Disastrous said:

Which is, simply, how on earth do you use them as dive watches/timers if the bezel is marked for a 24 hour clock??

Surely it defeats the point of a dive watch, if it can't be used to easily calculate elapsed time? Or am I missing something...?

I had a GMT dive watch and they got around the problem by not having the 24 hour markings on the bezel.

[Disastrous]

Debaser said:

Disastrous said:

Which is, simply, how on earth do you use them as dive watches/timers if the bezel is marked for a 24 hour clock??

Surely it defeats the point of a dive watch, if it can't be used to easily calculate elapsed time? Or am I missing something...?

I had a GMT dive watch and they got around the problem by not having the 24 hour markings on the bezel.

Like that a lot debaser. Very nice watch-still available?

[Debaser]

Disastrous said:

Debaser said:

Disastrous said:

Which is, simply, how on earth do you use them as dive watches/timers if the bezel is marked for a 24 hour clock??

Surely it defeats the point of a dive watch, if it can't be used to easily calculate elapsed time? Or am I missing something...?

I had a GMT dive watch and they got around the problem by not having the 24 hour markings on the bezel.

Like that a lot debaser. Very nice watch-still available?

Yep, you can still get them new.

Seiya in Japan sell them
http://www.seiyajapan.com/product/S-SBDB001/SEIKO-...

Or if you want to get one closer to home you can get them in Paris
http://www.seikocenter.fr/collections-exclusives/p...

[winstontongco]

a 2017 bump for a 2012 question...

read an article about this as I have the same itch..

from
http://insearchoftheperfectwatch.blogspot.com/2013...

AnonymousDecember 10, 2013 at 1:38 AM

Clearly you don't understand the diving function of the rotating bezel on the Omega PO (GMT).

Maybe they put the luminescent spot on the rotating bezel to use as a diving timer?
Example: you start diving at 10:30 am and have 20 minutes of oxygen.
Set the luminescent spot at the 10 o'clock hour marker (on the dial) and you'll know when to go back to the surface when the minute hand reaches that marker.

There's no need for the 24 hour markers on the bezel in the dark though ;-)

- Hope this helps!

[Wills2]

Omega put the 24 clock on the inside of the face of the PO GMT.

Edited by Wills2 on Wednesday 11th January 16:49

[hosedoctor]

You don't use a GMT watch for diving! You use a bezel with a one way rotation, GMT watches are for a different purpose not diving..

[Disastrous]

hosedoctor said:

You don't use a GMT watch for diving! You use a bezel with a one way rotation, GMT watches are for a different purpose not diving..

Of course, but then it looks odd to style them as dive watches and give them a massive depth rating, no?

[dc2rr07]

hosedoctor said:

You don't use a GMT watch for diving! You use a bezel with a one way rotation, GMT watches are for a different purpose not diving..

Unless you have an Omega like the one in Wills2 post

[hosedoctor]

Disastrous said:

hosedoctor said:

You don't use a GMT watch for diving! You use a bezel with a one way rotation, GMT watches are for a different purpose not diving..

Of course, but then it looks odd to style them as dive watches and give them a massive depth rating, no?

As I said a GMT watch isn't ment to be used as a dive watch its ment to tell the time in different time zone,s? A lot of manufacturers make watches with a good depth rating even if there not a dive watch? If that makes sense Lol.

[dc2rr07]

hosedoctor said:

Disastrous said:

hosedoctor said:

You don't use a GMT watch for diving! You use a bezel with a one way rotation, GMT watches are for a different purpose not diving..

Of course, but then it looks odd to style them as dive watches and give them a massive depth rating, no?

As I said a GMT watch isn't ment to be used as a dive watch its ment to tell the time in different time zone,s? A lot of manufacturers make watches with a good depth rating even if there not a dive watch? If that makes sense Lol.

Not really agreeing with you there, many people go on holiday diving so you have the GMT function as well as the dive function in one watch.

[Wills2]

hosedoctor said:

You don't use a GMT watch for diving! You use a bezel with a one way rotation, GMT watches are for a different purpose not diving..

The post above yours clearly shows a Planet Ocean with a one way rotating bezel with the addition of a GMT function courtesy of the 24hr clock within the face so it's as functional as a dive watch as any other PO.

But it's a nonsense anyway as you'd use a modern dive computer rather than a 10k Omega.