For this week’s Dive Watch Wednesday column, let’s put aside the question of how many mechanical dive watches are actually being used for diving today. Let’s instead assume that most of them are in fact being used for this intended purpose, and focus on the aspect of functionality.
As some of you may already know, colors behave quite a bit differently underwater, which is why the silent world often looks blue and green to a frequent diver (or mostly black after descending about 300 feet). Underwater, light waves travel differently, and some colors are filtered out by water sooner than others. Which means that, at about 20 feet, red is the first color to disappear underwater (if you don’t use a flash or flash light). This is also the reason why orange is used quite often for dials and hands on dive watches, since it tends to be one of the last colors to disappear. But back to the color red. The Tissot Seastar watch shown here (Ref. T19.1.593.51, introduced in 2003 and replaced in 2011 with the current range) is a great example for demonstrating this effect: Comparing the two pictures, you will immediately notice the radical change in appearance (i.e., on the minute indexes and Seastar logo). Red on a dark background therefore disappears, and on a light background simply turns dark. Sometimes, this effect is used intentionally (e.g. on some Sinn dive watches): unnecessary information is filtered out underwater, and the legibility of the watch increases. But there are still some dive watches with a “function follows style” approach in mind that unintentionally have red elements on the dial or bezel that disappear underwater.