There is no doubt that things that glow in some form or fashion capture our attention. Ever since I was a little kid, I liked things that glowed in the dark, and I see the same with my own children. For those into watches, that takes the form, generally, of checking out the luminous materials applied on to our watches (just check out #FridayNightLumeBattle or #Illuminauts on Instagram to see this in action). For me, I like fiddling about with all sorts of night-lighting on watches, be it luminous paint, LEDs, EL, or, as we have in the Deep Blue Daynight, tritium tubes.


Tritium lighting is one of those things that seems a bit underwhelming until you see it in person, most likely due to the photos you see (shooting small glowing bits in the dark requires a bit more work than your standard cell phone snap). Once you have the chance to check it out in person, then it is a whole new ball game. Sure, it may not have that “wow factor” the initial charge of SuperLuminova may give you, but it’s hard to be consistent output for 10+ years with no external inputs. It is also worth noting that there is only one company worlwide (at least that I am aware of) making the tritium tubes for watches, so you do not need to worry about the tubes themselves being of differing quality from brand to brand.


Really, when it comes to the tritium tubes, it’s more a question of if you’re looking for the standard tubes, or the newer flat tubes. Here on the Deep Blue Daynight, you have the standard tubes which make for quite handy indice markers, as well as taking the place of lume strips on the handset. Most brands using these tubes will pop a different color at the 12 o’clock position to help you figure out which way is up, and that is indeed what we have here. They have also gone with double tubes, which makes it more prevalent (a single flat tube would have sufficed here nicely). Interestingly, they also have double tubes on the hour hand, which is something I have not yet seen on a tritium-equipped watch. To do this, they needed to make a fairly large hour hand, and that’s what you have here.


Though, the tip of the hour hand on the Deep Blue Daynight is carved out a tad, so you have some of the visual bulk removed. For me, I rather like the broad arrowhead, and it seems fitting to me to have a large (and easily distinguishable) handset used on a watch like this, which is ostensibly a diver, with it’s 500m WR rating. Add in the tritium tube that calls the pip on the bezel home, and you have something ready to time your dive – or just a nightime walk through the neighborhood. For those using it in a more demanding situation, the change of colors (most of the tubes are blue, with orange showing up at the 12 o’clock position and on the hands) will keep things easy to read.


All of these tubes are tucked on a fairly tight dial (though, I could do with a bit less text on it). The dials come in either blue, black, orange, or silver, and it looks there will be a choice of two ceramic bezels (white or black). With the Deep Blue Daynight, you have a lot of higher-end stuff showing up in the 44mm steel case – a high WR rating, ceramic on the bezel, a sapphire crystal, and of course the tritium. To keep things affordable, the brand went with a well-known movement, the Miyota 9015, which is certainly the belle of the ball for the indie watch makes these days. While the movement may not stir up the passions, it is a very workable and reliable solution.


If you cannot tell from the writeup, I am rather keen on the Deep Blue Daynight, particularly the blue dial and white bezel combo. I am always glad to see another brand playing with tritium, and the hour hand implementation on the Deep Blue Daynight is the first I’ve seen with the double tubes. Deep Blue really seem to have been on a tear as of late with the watch introductions, and the $799 Deep Blue Daynight looks to be a worth addition to the lineup. If you run across one of these in person, be sure to let us know your thoughts, as I am curious how these look and feel, especially in comparison to the other sub-$1000 tritium divers on the market today.


Watch Overview

  • Brand & Model: Deep Blue Daynight Mil Ops
  • Price: $799 (currently on sale for $655)
  • Who we think it might be for: You’re looking for a diver with tritium
  • Would I buy one for myself based on what I’ve seen?: Yes, this one would be tempting, especially with the double-tube hour hand
  • If I could make one design suggestion, it would be: Test out the flat tube at least at 12 o’clock, if not also on the hour hand
  • What spoke to me the most about this watch: Narrowing it down to a single detail, its the hour hand.

Tech Specs from Deep Blue

  • 44mm case, 15mm thick, 22mm Lugs, 316L Stainless Steel 51mm L 2 L
  • Citizen Caliber 9015 Automatic Movement
  • Sapphire Crystal, 500 Meters – 1650 Feet
  • Ceramic Bezel with Tritium Tube at 12 oclock
  • Sunray dual circle Dial, Screw down crown and caseback
  • Tritium Markers on the Dial, Bezel, and hands
  • Tritium Dial Markers:
    • 12 O’Clock Position = 2 Orange Tubes
    • 1,2,3,4,5,6,7,8,9,10,11 = 1 BLUE Tube
    • Hands Orange Tubes- Hour hand 2 orange tubes – Minute hand 1 Orange Tube
  • Push button Deployant with Safety

ByPatrick Kansa

A big data developer and leader with a penchant for gadgets, books, watches and beverages. You can find my work on WristWatchReview, Knapsack.News, and Slushpile. If you're on Twitter and/or Instagram, you'll find me there as @PatrickWatches.

2 thoughts on “Lighting up the Night with the Deep Blue Daynight”
  1. I fully agree on having too much text on the dial, please reduce this. Also please start putting the date windows at 6 o’clock.

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