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Posted (edited)

Usually on most watches (anyway those that I have) have a shorter and wider hour hand and a thinner and longer minute hand. 

Well, that's what I thought until I latched on to a Rotary Chronospeed.

Can anyone explain the rationale for this watch to have a larger minute hand ?

I can only speculate since I have done some scuba diving.

Could it be that a diver doesn't care as much about the hour hand as much as the minute hand in a dark environment (we don't all swim in a wonderful clear and pristine ocean, our rivers and lakes in Canada can get quite murky with the river and lake silt).

A standard aluminum 80-cubic-foot tank on a 40-foot dive should allow for about 45 to 60 minutes.

Could it be that its easier to set the bezel with a larger minute hand ?

Do any other dive watches, or for that matter any other watch have this feature ?

And as you can see, this Rotary model has a really good lume for murky waters.:thumbsu:

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Edited by MilTimeCan
Posted

Well whodathunkit !

It took a bit of research, but I have discovered the rationale is for low light conditions and common for dive watches.

The Autozilla has a black plain dial that is adorned with long-lasting, super-luminous large hour markers. This enables reading the time in dim light situations with ease. The markers for 3, 6, 9 and especially 12 o'clock and the zero marker on its unidirectional rotating elapsed time bezel are conspicuously styled to prevent disorientation induced read out errors under the darkness of the seas. There is a day-date display at three o’clock position. The day and date of this watch can be quick-set.

The rugged looking rotating bezel have a minute scale going up to 60 minutes with a marking at every 5 minutes interval. It is easily detachable for cleaning after a dive. For a diver's watch the rotating device shall be protected against inadvertent rotation or wrong manipulation. The Autozilla also has a register ring clamp locking lever near its crown. 

For diving purposes, an indication that the watch is running in total darkness also has to be present. The Autozilla employed a running second hand with an arrow luminous tip. It also has a large, easily identifiable bright orange minute hand.  The hands design is also in such a way that no hand can totally overlay and hence obscure the position of another hand to prevent read out errors. Both minute and hour hands are heavily non-radioactive, photo-luminiscent treated.


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Source:  http://watchopenia.blogspot.ca/2014_06_01_archive.html 

and for 2017....

1474383926-helson.jpggallery-1456434842-seiko-srp775.jpgscurfa-dive-watch.jpeg

 

Source: http://www.bestproducts.com/mens-style/g1193/best-dive-watches-for-men/ 

  • Like 1
Posted
20 hours ago, ricardopalamino said:

I haven't paid much attention to rotary watches to date ,..but I sure do like yours .  Where are these watches made ?

Thanks , Louis

It won't appear on the Rotary site, its a recently discontinued model. I purchased this at a retailer who specializes in end of stock items. 

Posted (edited)
15 minutes ago, ricardopalamino said:

That article cleared it up for me . I thought the Rotary was made in England .

 

Once again MilTimeCan , ...that's a nice looking watch . Does that retailer have lower than new pricing ?

Thanks ...Yes, they do. You might be familiar with them, its the Canadian equivalent of TJ Maxx, our stores are called "Winners" . I have seen a few on eBay and Amazon.com

Edited by MilTimeCan
  • 1 month later...
  • 4 weeks later...
Posted

Scuba divers only need to know how many minutes they have used.

Set the  bezel pointer to where the minute hand is, you'll know how much time you have spent underwater. Knowing how long your tanks can last you can decide when you need to surface. The uni-directional is a fail-safe device, if you accidentally move it, you can only move i counter-clockwise. This means it will show that you have spent "more" time under water. As a result, you would surface earlier if you are purely depending on the minute hand. If the bezel could move clockwise, you might end up longer underwater.

As a point of interest, there are also count-down or elapsed time bezel where the numbers 0-60 run counter clockwise. Here you decide how much time you want to spend under-water, eg 10 minutes, set the bezel at the 10 minute mark and the minute hand will head progressively down to zero. Search Google images for  'count-down bezel' or 'elapsed time bezel'.. unfortunately I don't have any of these but alsways thought that made more sense for a diver.

Anil

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