More info. added (GS with "Chronometer" and GS Astronomical Observatory Chronometer

Jan 05, 2008,18:32 PM

Hi Steve, I would like to add some pieces of info. here in accordance with some Japanese documents I have.

1) There were only 2 GS models having the word "Chronometer" on them; namely a) the GS3180 released in 1960 (widely known as the GS first model) by Suwa Seiko, and b) the GS second model released in 1963 (GS430 for the first batch and GS5722A for the second batch -> both=18,000 vph) also by Suwa Seiko.

GS3180 (the GS first model) with "Chronometer" on its dial only

GS430 (the GS second model made in the first batch) with "Chronometer" on both its dial and its movement

GS5722A (the GS second model made in the second batch) with "Chronometer" on both its dial and its movement

It is noted that the GS second model made in the third & fourth (last) batches GS5722B no longer came with "Chronometer" but "GS" mark instead. The production start of GS5722B was estimated to be from 1966. Since Seiko was unable to use "Chronometer" any more, the Seiko's own stricter accuracy standard (than that of "Chronometer") was introduced, making Seiko increase the VPH of 5722B to 19,800 vph.

Your GS second model 5722B was the third batch in my opinion. It is typically understood that a difference between the 5722B third batch and the 5722B fourth batch is the size of a "GS" mark on the dial. The 5722B third batch came with a slimmer but taller "GS" mark in comparison with that of the 5722B fourth batch.

Your GS5722B (the GS second model made in the third batch)

GS5722B (the GS second model made in the fourth batch)


2) Concerning the GS Astronomical Observatory Chronometer, it was made by Kameido Seiko (Daini Seiko) based on the no-date GS45 model (36,000 vph). The GS45 is considered the last vintage hand-wound GS after GS3180, GS430 or 5722 and GS44 (known as the most mysterious GS).

Seiko marketed this GS45 Astronomical Observatory Chronometer (like GP Gyromatic Observatory Chronometer as you've mentioned) maybe in 1969. According to my documents, it was 73 out of 103, passing the Astronomical Observatory Chronometer. It was designated as 45GSN cased in 18KYG. The price in 1969 was 180,000 JPY, which was almost 2 times that of the GS45VFA (SS-cased) of 100,000 JPY.

45GSN Astronomical Observatory Chronometer (18KYG) -> Dial & Movement  

The Concour Certificates and the movements displayed at The Seiko Institute of Horology (Kameido, Tokyo)

Hope my info. given above helps add more contents to this very interesting topic.

Regards, Joe


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A Short History of the Grand Seiko

 By: SJX : January 4th, 2008-07:06
There is hardly any English language information available for Grand Seiko so I decided to put one together. I actually wrote a few words on this some years back, but never completed or published it. Since there has been substantial interest on the forum ...  

Great reading for GS fans... and for those who are not familiar with ...

 By: Horolographer : January 4th, 2008-08:50
the watches or have not seen a GS before. Thanks JX for a wonderful article. Cheers Harry

Wonderful summary, thank you

 By: Harry Bishop : January 4th, 2008-19:28

Fantastic read!! Thank you!!

 By: ks : January 4th, 2008-22:47
Do you happen to know if there is any dive watch series in Grand Seiko? Cheers! rgds ks

Thanks for the informative post about the GS.

 By: vlim : January 4th, 2008-23:18
I really have to take a closer look at their timepieces when the opportunity arises.

Thanks, SJX,

 By: masterspiece : January 5th, 2008-00:36

In two minds........

 By: MTF : January 5th, 2008-05:08

great read, but one particularly controversial passage

 By: ei8htohms : January 5th, 2008-07:41
Hi SJX, This is a great read and will likely serve to educate many Grand Seiko newbies for years to come. Thanks! I wantred to mention though that the often repeated bit about Seiko's success at the Observatory Competitions in Geneva and Neuchatel being r... 

Some thoughts on the controversy...

 By: SJX : January 5th, 2008-08:08
Hi ei8htohms, Thanks for the input. That's a good point and I do agree with it; that the discontinuation of the observatory trials due to the success of the Japanese can never be proven with any certainty, whatever is said is conjecture and personal opini... 

Great read, JiaXian, ....

 By: SuitbertW : January 5th, 2008-09:42
and a worthy subject as well. Re. the observatory chronometer competitions - I don't share your view on this, and I'd be curious to see the data you seem to have found. In 1968 - to my knowledge the Geneva chronometer competitions were already gone - i.e.... 

some info

 By: ei8htohms : January 5th, 2008-10:41

Like I wrote earlier Suibert...

 By: SJX : January 5th, 2008-19:20
I appreciate your comments; I look forward to your posts because they are always very informative. Like I wrote earlier, in agreement with John, whether the demise of the observatory trials is due to the quartz revolution or Japanese watches or anything e... 

Hi JiaXian, ....

 By: SuitbertW : January 6th, 2008-03:57
...don't take me wrong, I'm not going to convince you or attempting to change your opinion. But I found the facts on which you obviously based this opinion a bit puzzling. As John pointed out the reference to J. Goodall's - I'm going to see where the data... 

A reply

 By: SJX : January 6th, 2008-04:31

The source I have read which somewhat addresses this

 By: SteveG : January 5th, 2008-10:30
question, more in an informational rather than rhetorical fashion, is K. Seiya: At this page: .html#chrono ) "Chronometer appeal In the middle of 1960's, European Chronometer Official Association appealed that Seiko shouldn't use the name ... 

More info. added (GS with "Chronometer" and GS Astronomical Observatory Chronometer

 By: JoeT : January 5th, 2008-18:32
Hi Steve, I would like to add some pieces of info. here in accordance with some Japanese documents I have. 1) There were only 2 GS models having the word "Chronometer" on them; namely a) the GS3180 released in 1960 (widely known as the GS first model) by ...  

Thanks JoeT

 By: SJX : January 5th, 2008-19:22

Wow, great post, thanks! nt

 By: Chris Meisenzahl : January 5th, 2008-17:33

Thanks for a good read.

 By: yw wong : January 6th, 2008-08:40

Setting the record straight - I hope

 By: ticktock : January 6th, 2008-16:36
As the author of "A Journey in Time: The Remarkable Story of Seiko" which was one of the references used by SJX, it seems appropriate to post here Seiko's official description of the Spring Drive mechanism, as quoted in the press release issued at the tim... 

Thanks for the post.

 By: SJX : January 6th, 2008-18:16

Great stuff!

 By: masterspiece : January 7th, 2008-10:02

excellent report!!! [nt]

 By: The Curious Observer : January 10th, 2008-20:25