Dual Time vs GMT
- jkbarnes
- Senior Forumgod
- Posts: 7852
- Joined: Wed May 24, 2017 8:39 pm
- CW-watches: 3
- Location: Virginia, USA
Dual Time vs GMT
Are these terms synonyms or is there a difference between a dual time watch vs. a GMT complication? Perhaps there was a difference at one point but they’re now used interchangeably? Or are they NOT used interchangeably? Or maybe the difference in terms reflects how the second time is presented?
The question is prompted by browsing a watch brand’s site and seeing some watches labeled “dual time” while another was “GMT.”
The question is prompted by browsing a watch brand’s site and seeing some watches labeled “dual time” while another was “GMT.”
Drew
- Amor Vincit Omnia
- Moderator
- Posts: 33793
- Joined: Sat Jun 11, 2011 7:34 pm
- CW-watches: 4
- Location: Norfolk, UK
Re: Dual Time vs GMT
I have often wondered about this too, Andrew. I think that in a lot of people’s minds the differences are shrouded in mystery, especially when we add in the world timer description.
My basic understanding (and forgive me if I am wrong here) is that a dual time might be something as simple as an adjustable bezel such as the internal one which the Magrette Dual Time has.
As far as I know a GMT can be a watch such as the ones produced by CW, where the third hand is independently adjustable. This is distinct from what tends to be called a True GMT, such as the ones produced by Rolex, where there is an independently adjustable hour hand.
To my mind a world timer seems to suggest that there should be a ring of time zones with prominent cities to identify them. I think in other respects the CW world timer (at least the C65 variant) is just a standard GMT movement with that addition.
The two CW world timers with JJ movements are a bit different. I have also seen watches (including vintage) with a completely separate subdial that operates as a second time zone in miniature.
Clear? As mud, I suspect!
My basic understanding (and forgive me if I am wrong here) is that a dual time might be something as simple as an adjustable bezel such as the internal one which the Magrette Dual Time has.
As far as I know a GMT can be a watch such as the ones produced by CW, where the third hand is independently adjustable. This is distinct from what tends to be called a True GMT, such as the ones produced by Rolex, where there is an independently adjustable hour hand.
To my mind a world timer seems to suggest that there should be a ring of time zones with prominent cities to identify them. I think in other respects the CW world timer (at least the C65 variant) is just a standard GMT movement with that addition.
The two CW world timers with JJ movements are a bit different. I have also seen watches (including vintage) with a completely separate subdial that operates as a second time zone in miniature.
Clear? As mud, I suspect!
Steve
Linguist; retired teacher; pilgrim; apprentice travel writer
Take nothing but pictures, leave nothing but footprints, kill nothing but time
Avoid loud and aggressive persons; they are vexatious to the spirit. (Max Ehrmann)
Linguist; retired teacher; pilgrim; apprentice travel writer
Take nothing but pictures, leave nothing but footprints, kill nothing but time
Avoid loud and aggressive persons; they are vexatious to the spirit. (Max Ehrmann)
Re: Dual Time vs GMT
I take the view that a watch described as a GMT would typically have the time in the 2nd time zone indicated by a hand pointing to a 24 hour scale, depicted on either an external bezel, or an internal rehaut. I.e. designs that are a nod to the original Rolex GMT Master that was designed for Pan Am pilots.
A dual time watch tends (but not always) to have the 2nd time zone on a simple 12 hour scale, either by use of a sub dial, or occasionally another hour hand on the main dial, that is only visible when a different time zone is being selected. The so called dual time complication often has an AM/PM indicator for the 2nd time zone. Pushers, rather than use of a position on the crown are sometimes used to set the 2nd time zone.
Neil
A dual time watch tends (but not always) to have the 2nd time zone on a simple 12 hour scale, either by use of a sub dial, or occasionally another hour hand on the main dial, that is only visible when a different time zone is being selected. The so called dual time complication often has an AM/PM indicator for the 2nd time zone. Pushers, rather than use of a position on the crown are sometimes used to set the 2nd time zone.
Neil
Other watch forums of interest:
TZ-UK
TZ-UK
- tikkathree
- Trusted Seller
- Posts: 7363
- Joined: Fri Jan 24, 2014 12:21 am
- CW-watches: 1
- Location: East Anglia - arr 'aas right buh
Re: Dual Time vs GMT
My experience has proven the two terms to be used synonymously and that watchmakers usually go for the catchier GMT moniker.
When I talk about a GMT watch I really mean dual time zone because my interest is in tracking the actual time with my siblings, 7 hours behind London time.
There are watches which simply have a 24hour bezel, often but not exclusively in "pepsi" fashion or have a 24 hour subdial. Within my experience these cannot be set independently of the main hands.
Let's see now...
C65 Anthropocene: I use both the pointer and subdial to represent "Wyoming time"
My C60 GMTs I leave the bezel alone and rely on the pointer
Sorry about the dust.... Ditto the Great White
Or you could have subdial Second Time Zone
Then Omega does the 24hour marker in a subdial
Or, howabout an independently set GMT/Second Time Zone hand? The watch runs down and stops and you lose the differentiation. Bet you wish you hadn't woken me up now....
When I talk about a GMT watch I really mean dual time zone because my interest is in tracking the actual time with my siblings, 7 hours behind London time.
There are watches which simply have a 24hour bezel, often but not exclusively in "pepsi" fashion or have a 24 hour subdial. Within my experience these cannot be set independently of the main hands.
Let's see now...
C65 Anthropocene: I use both the pointer and subdial to represent "Wyoming time"
My C60 GMTs I leave the bezel alone and rely on the pointer
Sorry about the dust.... Ditto the Great White
Or you could have subdial Second Time Zone
Then Omega does the 24hour marker in a subdial
Or, howabout an independently set GMT/Second Time Zone hand? The watch runs down and stops and you lose the differentiation. Bet you wish you hadn't woken me up now....
C60 MKI, MKII, MKIII: "some",
C6 & C60 Kingfishers,
C600 Tritechs,
C63 "some",
C65 "some",
C4, C40, C8, C9, C3, C5, C20 & 23FLE
Some other brands
C6 & C60 Kingfishers,
C600 Tritechs,
C63 "some",
C65 "some",
C4, C40, C8, C9, C3, C5, C20 & 23FLE
Some other brands
- jkbarnes
- Senior Forumgod
- Posts: 7852
- Joined: Wed May 24, 2017 8:39 pm
- CW-watches: 3
- Location: Virginia, USA
Re: Dual Time vs GMT
Haha! I didn’t even think about a world timer! I’ve never fully understood exactly what a world timer is.Amor Vincit Omnia wrote: ↑Tue Jul 14, 2020 4:46 pm I have often wondered about this too, Andrew. I think that in a lot of people’s minds the differences are shrouded in mystery, especially when we add in the world timer description.
My basic understanding (and forgive me if I am wrong here) is that a dual time might be something as simple as an adjustable bezel such as the internal one which the Magrette Dual Time has.
As far as I know a GMT can be a watch such as the ones produced by CW, where the third hand is independently adjustable. This is distinct from what tends to be called a True GMT, such as the ones produced by Rolex, where there is an independently adjustable hour hand.
To my mind a world timer seems to suggest that there should be a ring of time zones with prominent cities to identify them. I think in other respects the CW world timer (at least the C65 variant) is just a standard GMT movement with that addition.
The two CW world timers with JJ movements are a bit different. I have also seen watches (including vintage) with a completely separate subdial that operates as a second time zone in miniature.
Clear? As mud, I suspect!
As for the rest of your response, I think you’ve captured the difference perfectly! To paraphrase Winston Churchill, the difference appears to be a riddle wrapped up in an enigma?
On a serious note, I was wondering if perhaps GMT implied an 24 hour central hand with an adjustable bezel, while a dual time suggested a subdial with either a 24 hour hand or 12 hour hand?
Drew
- jkbarnes
- Senior Forumgod
- Posts: 7852
- Joined: Wed May 24, 2017 8:39 pm
- CW-watches: 3
- Location: Virginia, USA
Re: Dual Time vs GMT
That’s what I was thinking when I posed the question.nbg wrote: ↑Tue Jul 14, 2020 5:04 pm I take the view that a watch described as a GMT would typically have the time in the 2nd time zone indicated by a hand pointing to a 24 hour scale, depicted on either an external bezel, or an internal rehaut. I.e. designs that are a nod to the original Rolex GMT Master that was designed for Pan Am pilots.
A dual time watch tends (but not always) to have the 2nd time zone on a simple 12 hour scale, either by use of a sub dial, or occasionally another hour hand on the main dial, that is only visible when a different time zone is being selected. The so called dual time complication often has an AM/PM indicator for the 2nd time zone. Pushers, rather than use of a position on the crown are sometimes used to set the 2nd time zone.
Neil
Drew
- Amor Vincit Omnia
- Moderator
- Posts: 33793
- Joined: Sat Jun 11, 2011 7:34 pm
- CW-watches: 4
- Location: Norfolk, UK
Re: Dual Time vs GMT
As in, “What’s the current time in Byzantium, Publius?”
Steve
Linguist; retired teacher; pilgrim; apprentice travel writer
Take nothing but pictures, leave nothing but footprints, kill nothing but time
Avoid loud and aggressive persons; they are vexatious to the spirit. (Max Ehrmann)
Linguist; retired teacher; pilgrim; apprentice travel writer
Take nothing but pictures, leave nothing but footprints, kill nothing but time
Avoid loud and aggressive persons; they are vexatious to the spirit. (Max Ehrmann)
- jkbarnes
- Senior Forumgod
- Posts: 7852
- Joined: Wed May 24, 2017 8:39 pm
- CW-watches: 3
- Location: Virginia, USA
Re: Dual Time vs GMT
STUPID AUTOCORRECT!Amor Vincit Omnia wrote: ↑Tue Jul 14, 2020 5:23 pmAs in, “What’s the current time in Byzantium, Publius?”
I literally laughed out loud at this!
I’ll go back and fix that...
Drew
- jkbarnes
- Senior Forumgod
- Posts: 7852
- Joined: Wed May 24, 2017 8:39 pm
- CW-watches: 3
- Location: Virginia, USA
Re: Dual Time vs GMT
Not at all! I think all those examples serve to validate my question.tikkathree wrote: ↑Tue Jul 14, 2020 5:07 pm Let's see now...
Bet you wish you hadn't woken me up now....
And I really wish that Anthropocene came in a non-LE version. That’s a beautiful watch.
Drew
-
- Trusted Seller
- Posts: 1329
- Joined: Thu Mar 15, 2018 11:46 pm
- CW-watches: 4
- Location: Cambridgeshire
Re: Dual Time vs GMT
I’m a little late to this but I have a small collection of travellers watches & they are my most used variety because I travel a lot for work, or at least I used to.
When I hear “dual time watch”, I think of a watch with a rotating 12-hour bezel or a chapter ring, which is offset so the main hour hand points to a different timezone. The Magrette Dual Time mentioned by AVO is an example, but any watch with a moving 12 hour bezel will do the same thing. I’ve blagged one of Gary’s pictures below (credit where it’s due).
GMTs usually have an extra “GMT” hand - usually red, orange, yellow, even blue, which can be set independently to point to any hour, but moves at half speed (1 full rotation per 24 hours), therefore tracking a second timezone. Many GMTs, including the CW C60 & C65 versions, and the Zelos below, use ETA or Sellita movements, which allow the GMT hand be set independently.
A better design, in my opinion is to allow the main hour hand to be set independently, which is how the Rolex GMT Master (I think) & the Tudor BB work. This is a lot more practical if you are on the move. I use the Tudor when I travel long haul with connections in different places, because I can easily set the main hour to local time.
Worldtimers are different again - they are meant to easily show the time in any timezone in the world. They usually have a rotating inner bezel showing the names of different (sometimes relatively little known) cities around the world. By setting the GMT hand to, errr, GMT, & aligning the target city on the inner bezel to 12, the GMT hand should show the time in that city. On this Bremont you can see that it’s just after 9pm in the UK, and just after 3pm in Chicago (this watch also operates as a traditional ETA GMT).
The key is that the inner bezel should rotate. If my memory serves me correctly, the CW C65 Worldtimer doesn’t have a rotating bezel, but I haven’t handled it so I’m not sure exactly how it works.
There are versions of Worldtimers which use different displays - CW makes one with a map of the world and little red dots, though I don’t really understand how it works.
I also have an Oris Worldtimer, which is not really a Worldtimer, & operates in a different way to all the others. It has a separate sub-dial at 3 for the home time, while push buttons at 4 & 8 shift the main hour hand forward & back, and for the same reason I mention above with the Tudor GMT, it fabulously practical when travelling.
There may be other variants out there, and if there are, I’d be fascinated to hear how they work.
When I hear “dual time watch”, I think of a watch with a rotating 12-hour bezel or a chapter ring, which is offset so the main hour hand points to a different timezone. The Magrette Dual Time mentioned by AVO is an example, but any watch with a moving 12 hour bezel will do the same thing. I’ve blagged one of Gary’s pictures below (credit where it’s due).
GMTs usually have an extra “GMT” hand - usually red, orange, yellow, even blue, which can be set independently to point to any hour, but moves at half speed (1 full rotation per 24 hours), therefore tracking a second timezone. Many GMTs, including the CW C60 & C65 versions, and the Zelos below, use ETA or Sellita movements, which allow the GMT hand be set independently.
A better design, in my opinion is to allow the main hour hand to be set independently, which is how the Rolex GMT Master (I think) & the Tudor BB work. This is a lot more practical if you are on the move. I use the Tudor when I travel long haul with connections in different places, because I can easily set the main hour to local time.
Worldtimers are different again - they are meant to easily show the time in any timezone in the world. They usually have a rotating inner bezel showing the names of different (sometimes relatively little known) cities around the world. By setting the GMT hand to, errr, GMT, & aligning the target city on the inner bezel to 12, the GMT hand should show the time in that city. On this Bremont you can see that it’s just after 9pm in the UK, and just after 3pm in Chicago (this watch also operates as a traditional ETA GMT).
The key is that the inner bezel should rotate. If my memory serves me correctly, the CW C65 Worldtimer doesn’t have a rotating bezel, but I haven’t handled it so I’m not sure exactly how it works.
There are versions of Worldtimers which use different displays - CW makes one with a map of the world and little red dots, though I don’t really understand how it works.
I also have an Oris Worldtimer, which is not really a Worldtimer, & operates in a different way to all the others. It has a separate sub-dial at 3 for the home time, while push buttons at 4 & 8 shift the main hour hand forward & back, and for the same reason I mention above with the Tudor GMT, it fabulously practical when travelling.
There may be other variants out there, and if there are, I’d be fascinated to hear how they work.
My name is 0uatiOW, but before you ask, no I don’t.
“Exquisitely minging” MissF, 19 July 2022
Just call me Diderot
“Exquisitely minging” MissF, 19 July 2022
Just call me Diderot
Re: Dual Time vs GMT
When I was travelling for work, the watch that always appealed tome was the JLC Master Hometime...
The blue second hour hand shows ‘hometime’ on a 12 hr scale, while the main hour shows local. Hometime is also shown on a 24 hour scale on the upper subdial. When you are in your home time zone, the second hour hand is hidden behind the main hour hand.
The blue second hour hand shows ‘hometime’ on a 12 hr scale, while the main hour shows local. Hometime is also shown on a 24 hour scale on the upper subdial. When you are in your home time zone, the second hour hand is hidden behind the main hour hand.
Richard
- jkbarnes
- Senior Forumgod
- Posts: 7852
- Joined: Wed May 24, 2017 8:39 pm
- CW-watches: 3
- Location: Virginia, USA
Re: Dual Time vs GMT
That’s a real beauty, and a rather elegant execution of dual times.downer wrote: ↑Tue Jul 14, 2020 10:35 pm When I was travelling for work, the watch that always appealed tome was the JLC Master Hometime...
The blue second hour hand shows ‘hometime’ on a 12 hr scale, while the main hour shows local. Hometime is also shown on a 24 hour scale on the upper subdial. When you are in your home time zone, the second hour hand is hidden behind the main hour hand.
Drew
- jkbarnes
- Senior Forumgod
- Posts: 7852
- Joined: Wed May 24, 2017 8:39 pm
- CW-watches: 3
- Location: Virginia, USA
Re: Dual Time vs GMT
Excellent and incredibly informative reply. Thank you!0uatiOW wrote: ↑Tue Jul 14, 2020 9:53 pm I’m a little late to this but I have a small collection of travellers watches & they are my most used variety because I travel a lot for work, or at least I used to.
When I hear “dual time watch”, I think of a watch with a rotating 12-hour bezel or a chapter ring, which is offset so the main hour hand points to a different timezone. The Magrette Dual Time mentioned by AVO is an example, but any watch with a moving 12 hour bezel will do the same thing. I’ve blagged one of Gary’s pictures below (credit where it’s due).
GMTs usually have an extra “GMT” hand - usually red, orange, yellow, even blue, which can be set independently to point to any hour, but moves at half speed (1 full rotation per 24 hours), therefore tracking a second timezone. Many GMTs, including the CW C60 & C65 versions, and the Zelos below, use ETA or Sellita movements, which allow the GMT hand be set independently.
A better design, in my opinion is to allow the main hour hand to be set independently, which is how the Rolex GMT Master (I think) & the Tudor BB work. This is a lot more practical if you are on the move. I use the Tudor when I travel long haul with connections in different places, because I can easily set the main hour to local time.
Worldtimers are different again - they are meant to easily show the time in any timezone in the world. They usually have a rotating inner bezel showing the names of different (sometimes relatively little known) cities around the world. By setting the GMT hand to, errr, GMT, & aligning the target city on the inner bezel to 12, the GMT hand should show the time in that city. On this Bremont you can see that it’s just after 9pm in the UK, and just after 3pm in Chicago (this watch also operates as a traditional ETA GMT).
The key is that the inner bezel should rotate. If my memory serves me correctly, the CW C65 Worldtimer doesn’t have a rotating bezel, but I haven’t handled it so I’m not sure exactly how it works.
There are versions of Worldtimers which use different displays - CW makes one with a map of the world and little red dots, though I don’t really understand how it works.
I also have an Oris Worldtimer, which is not really a Worldtimer, & operates in a different way to all the others. It has a separate sub-dial at 3 for the home time, while push buttons at 4 & 8 shift the main hour hand forward & back, and for the same reason I mention above with the Tudor GMT, it fabulously practical when travelling.
There may be other variants out there, and if there are, I’d be fascinated to hear how they work.
That Oris Worldtimer seems like the perfect travel watch. I love it.
Drew
Re: Dual Time vs GMT
Had a couple of versions of the Oris “Worldtimer” myself - back in the day...
Richard
- monkeymax
- Senior Guru
- Posts: 584
- Joined: Sat May 01, 2010 10:30 pm
- CW-watches: 3
- Location: South England
Re: Dual Time vs GMT
Some great examples in this thread! Here's an example that's definitely dual time rather than GMT!
-
- Similar Topics
- Replies
- Views
- Last post