Fenix Outfitters        
Results 1 to 3 of 3

Thread: Watch Review: Nite HAWK T100 (Tritium GTLS Self-illuminated)

  1. #1
    Flashaholic* subwoofer's Avatar
    Join Date
    May 2010
    Hove, UK

    Default Watch Review: Nite HAWK T100 (Tritium GTLS Self-illuminated)

    Perhaps a slightly tenuous link to my main specialisation in all things light emitting, but thanks to Nite, I have been able to take a close look at their T100 (or just 'T') rated self-illuminated HAWK watch.

    Nite, for those that are not familiar with them, are a British company specialising in the production and direct sale of permanent self-illuminated watches using tritium light sources known as GTLS.

    The majority of GTLS equipped watches are rated at T25 but the HAWK is extra bright due to being fitted with the maximum permitted quantity of tritium giving it its T100 rating (more on what this actually means later).

    Initial Impressions:

    When it first arrived, the complete package was very light weight, almost to the point I wondered if the outer box was empty. However, this is a super-light watch, so it was a promising start.

    Considering the light weight I was surprised to find the full presentation box included (also lightweight) and when opening the box you find the HAWK is very well presented, as it should be considering this is listed as one of the key product features.

    When I first discovered the HAWK, I was concerned about the specified size of a 51mm case diameter. I have big watches and have tried some you would struggle to get through a doorway, but I prefer them not to be too big. Maybe due to its light weight, the HAWK does not feel too large, it feels perfectly normal in size. All of its features seem well balanced, so the actual size seems ……well pretty normal actually.

    Opened in daylight, the true 'feature' of the HAWK's T100 GTLS illumination was as yet hidden from view. So of course I simply cupped my hand over the face and peered into my hands, and there it was, clearly illuminated with my eyes in 'daylight' mode. Can't wait for it to get dark!

    What is in the box?:

    A quick look over how it arrives. After eagerly tearing off the outer postal packaging, you find the plain black outer cardboard box.

    This is protecting the presentation box which features mock-leather with feature stitching round the edge.

    Flipping open the box lid, and inside you find the HAWK wrapped round a black pillow. Looking closer you can see the plastic protector on the K1 mineral glass.

    Stripping off the protector and you get the first proper view of the HAWK.

    What is GTLS/self-illuminated/Tritium?:

    This review is intended to be readable by both watch enthusiasts and those with only a passing interest. So to cater for all audiences I am going to include some more information regarding certain features of the HAWK, but in a general way.

    So we have seen T100, T25, GTLS, self-illuminated and Tritium mentioned. What are these, and are they safe?

    Since watches first needed to be read in total darkness, there have been many different approaches attempted, but the most reliable have been those using a radioactive energy source to provide light.

    'Woah! Radioactive! That must be dangerous' you might say. Well to start with it was. The first glow-in-the-dark paint was invented in 1902 and used dangerous radioactive materials (radium salts) to provide the energy. These were then used during World War 1 to allow soldiers to read watches and instruments at night. It became apparent soon after that this was not a good idea. So enter the GTLS.

    GTLS is simply 'Gaseous Tritium Light Source' and consists of a laser sealed glass tube with a phosphor coating which is filled with Tritium gas.

    Tritium is a radioactive gas which emits beta particles (or electrons) as it decays. These electrons have low energy and cannot escape the glass tube. Instead they 'excite' the phosphor coating inside the tube causing it to give off light.

    So this is where the term self-illuminating comes from, in that the GTLS vials give off light with no additional power source.

    Tritium is an unstable isotope with a half-life of 12.32 years. Half-life is a term used with radioactive materials to describe how long it takes for the radioactivity to reduce by half the initial amount. What this means in practice is that a tritium light source loses half its brightness in the half-life period.

    The more Tritium that is initially sealed in the phosphor lined tube, the brighter it will be to start with, and the longer it will still provide useful light.

    For those who are more aware of potential hazards from radioactive sources (with the beta radiation having virtually no penetrative ability) there is also the factor of other emission due to Bremsstrahlung. Bremsstrahlung is secondary radiation that is released as a result of the charged particle (the electron) being slowed by another charged particle. However due to the low energy of the beta radiation, the most energetic secondary radiation will be UltraViolet light which itself only assists in further exciting the phosphor.

    There is no danger of exposure to radiation through the wearing of GTLS watches and the only possible exposure would be if you broke the GTLS vials and released the tritium. Even if this did happen the gas would diffuse quickly and the exposure would be negligible.

    To put this in perspective, if you ever used an old fashioned TV sets (cathode-ray tube types), these consisted of an electron gun firing electrons into a phosphor screen – which you sat in front of. Far higher amounts of 'activity' were present in these devices than a GTLS watch.

    One point you should be aware of is that from the time of manufacture, GTLS vials are gradually degrading due to the decay of the tritium, so they are only at their optimum at the point of manufacture. With the half-life being over 12 years this is not an issue in practice, but may be a consideration if buying a second-hand GTLS watch (it is good to know how old it is).

    The T25 and T100 designations refer to the initial 'quantity' of radioactivity. This also refers to the specific initial maximum value. So a T25 designation means it has a maximum level of radioactivity of 25 millicuries (or 25 mCi) at the time of manufacture. T100 is the greatest licensed quantity allowable for a watch, and the HAWK is extra bright due to being fitted with GTLS vials having the maximum permitted quantity of Tritium (with total radioactivity of over 25mCi and less than 100mCi).

    T, or T100 watches have a longer useful life due to the initially higher amount of Tritium present, so should be good for 25+ years and will still be glowing in 50-60 years.

    One further factor you should consider is the apparent brightness of different colours of GTLS vial. The eye is most sensitive to green light, therefore green GTLS vials will always appear brighter to the eye than any other colour.

    The HAWK mainly uses green vials (so the most visible) with orange used for the 12 o'clock marker. The orange GTLS does appear slightly dimmer and due to the eye's sensitivity can appear less than half the brightness of the green (orange is considered to have only 40% of the apparent brightness of green). In real use this is does not cause any issue with the orange vials being perfectly visible.

    Nite have confirmed that at time of manufacture, the mCi values for the HAWK are:

    Hour hand: 2.2 mCi
    Minute hand: 3.6 mCi
    Second hand: 1.21 mCi
    Dial: 47.52 mCi
    Bezel: 0.96 mCi

    The collective total of all the vials on the HAWK is 55.49 millicuries.

    The HAWK in detail:

    Now for a closer look at the HAWK, starting with an overall view of the watch laid flat.

    As with the glass, the silicone strap's buckle arrives with a protective plastic cover to ensure it reaches you in perfect condition. The buckle is PVD coated stainless steel.

    Peeling this off shows the Nite logo etched into the buckle and flawless black PVD (Physical Vapour Deposition) finish.

    The case is carbon-fibre reinforced polycarbonate, allowing the HAWK to be super tough and super lightweight. The bezel is made of the same material and has a unidirectional 60 click action.

    K1 mineral glass was chosen for the HAWK for several reasons. Due to the size of the HAWK casing a large expanse of glass is needed. Sapphire Glass would have to be too thick increasing the price and weight of the HAWK. With light weight being a key feature of the HAWK, this small compromise had to be made.

    The glass itself does not stand proud, so is partially protected by the bezel, and K1 has better scratch resistance to normal mineral glass, so hopefully this is will not affect long term condition too much.

    In daylight the vials appear nearly white against the dark grey fact. The hour and minute hand are a light grey colour to match the text printed on the face. The second hand (which also has a GTLV vial) is red and easily visible.

    Just like the strap buckle, the back of the HAWK also arrives with protective plastic.

    The stainless steel back has a PVD matt black finish and key feature information etched into the surface.

    The crown, which is made of the same material as the case and bezel, has the Nite logo impressed into it.

    The bezel has a small GTLS vial in the 12 o'clock / 60 position. The HAWK also has a day numeral.

    The back is retained by four screws. Nite recommend that this is only removed by a qualified watch technician, however I personally replace all my own watch batteries and this design makes it very easy (just make sure you match the threads back up when replacing the screws to prevent damage to the case and screw holes). If you do wish to change the battery yourself the HAWK uses a Renata Silver Oxide 371 battery.

    A close up of the screw.

    The HAWK features a new design strap. The strap is thicker and has two strap loops.

    A nice feature of the HAWK's strap is the thicker strap end which prevents the retaining loop slipping off the end of the strap while you wear it. This makes for excellent stability while wearing.

    To give a better idea of size, the HAWK is shown on a grid. The scale shown is in centimetres (with millimetre marks included).

    The HAWK's size is actually the result of customer requests to Nite for a larger watch. With the design incorporating the larger flat GTLS vials, the face also needed to be a certain minimum size to accommodate these larger vials without becoming over crowded.

    Weighing in at 64g, it is a super-light watch, despite the size.

    As darkness approaches there is a tantalising hint of the GTLS glow….

    Quartz movement and second hand alignment

    As with the GTLS section, this is intended to give some general information that may be of interest.

    Back in the old days, watch makers made their own movements, but since the advent of the quartz watch a lot has changed. Now, the majority of watches use movements made by a few specialist movement manufacturers.

    The HAWK uses a Swiss Ronda 515 movement which is a low power movement with date function.

    This leads me to comment on a 'feature' of many quartz movement watches, that of second hand alignment with the minute markers on the dial, to give a better understanding of what is going on and to moderate expectations.

    Manual wind and automatic clockwork movements run at a frequency of 28,800 beats per hour, for top end movements, (or 21,600 BPH for mid range movements down to the older traditional watches at 18,000 BPH) generally giving 5-8 movements of the second hand per second. This results in a slightly stuttering 'sweep' of the second hand rather than a 'tick'.

    Quartz movements generally move the second hand once a second, so 'tick'. This makes the alignment of the second hand with the minute markers more apparent, and is generally not perfectly aligned with the minute markers.

    In this exposure of over 1s, the second hand appears twice, showing the full 'tick' motion and the position of the second hand relative to the minute markers.

    This lack of perfect alignment is of no real concern (unless it bugs you personally) as it does not affect accuracy, and can slightly alter over time.

    With low power movements, the gearing is purposefully made looser to reduce friction and power usage. This means there is more 'backlash' in the gearing and a slightly sloppier positioning of the second hand. (This effect is also particularly visible in non-direct drive second hands in other movements)

    So it is normal to expect a quartz movement watch to have a second hand that does not perfectly align with the minute markers. This can be seen in watches costing many thousands of Pounds/Dollars.

    As well as low power movements, there are a limited number of high-accuracy quartz movements. The Ronda 515 is not one of these, so is subject to the typical average accuracy for quartz of +/- 15s per month.

    Testing the HAWK I have observed a 9s gain in 3 weeks making this approximately +/- 12s per month.

    Nite have chosen the largest battery that will fit in the Ronda 515, a 45 month Renata Silver Oxide 371 battery.

    The HAWK, day and Nite

    This is where the HAWK comes fully to life – after dark….

    With the watch in a fixed position and 'Tick-Tock' ….. Nite-Day…

    The exposure is set to represent the brightness visible once your night vision starts to kick in, but even straight from daylight, the HAWK's illumination is easy to see if you walk into a dark room.

    In the following animation, a time lapse set of photos were taken with the HAWK next to a watch with the brightest lume of any watch I have (LumiNova). This was fully charged with a UV light source just prior to the first photo being taken and the time lapse run from dusk till dawn.

    This clearly shows how the basic 'lume' fades out after a few hours, but the HAWK's GTLS continues to glow steadily all through the night.

    To finish off this section, it is important to put T100 into perspective. Here the HAWK is shown next to a T25 watch – need I say more?

    What is it really like to use…

    Due to the light weight, the size seems no issue at all. Of all my non-dress watches (I use only very low profile watches at work as I wear a suit), the HAWK is most easily forgotten until I want to know the time.

    My wrist seems to be average in size as I tend to use the middle holes on most straps, and I have found the HAWK very comfortable. The HAWK's strap looks as if it will accommodate a very large wrist as I have found that I am using a hole closer to the case than I normally would.

    When first using the strap, the strap loops were difficult to move as they seemed to drag over the strap, but this has got much easier with more use. The thicker strap end means the loops never move off the end of the strap without you moving them.

    The bezel rotation is tight and the clicks very positive. The bezel only rotates in one direction and has 60 stops.

    The GTLS is bright enough to see immediately in the dark even before your eyes have adjusted and as a very personal observation, when my eyes are completely dark adapted I can actually use the HAWK as a torch at close ranges. Despite this, it is not so bright as to disturb myself or my wife (who is very sensitive to stray light) at night and is comfortable to look at directly in the night for an immediate reading of the time.

    As mentioned in the GTLS section, you can notice that the orange 12 o'clock tubes are not as bright as the green flat tubes and appear a very pale orange. In some photos the orange can appear more orange than to the naked eye.

    I've noticed the flat tubes have a lower apparent surface brightness to the round tubes. However, as they have a much larger surface area, they do output a lot of light altogether.

    The HAWK also has a very quiet tick. I cannot normally bear to have a ticking watch on my bedside table, but I cannot hear the HAWK unless I put it to my ear. As it has excellent GTLS I wanted to have it by the bed, so this is an excellent feature.

    With the orange 12 o'clock markers, the GTLS equipped bezel and the fact all three hands are fitted with GTLS vials, apart from the date, the HAWK has its full capabilities available in total darkness.

    Personally I would probably prefer a slightly smaller overall case size, but the HAWK is so easy to live with. Its weight means you easily forget it is on your wrist and the instant readability of the time in any light conditions makes it a reliable companion.

    Test sample provided by Nite International for review.
    Tactical Reviews by Subwoofer
    Latest Reviews - @TacticalReviews and Facebook
    CandlePower Forums "Trusted Product Tester / Reviewer"

  2. #2
    Flashaholic* subwoofer's Avatar
    Join Date
    May 2010
    Hove, UK

    Default Re: Watch Review: Nite HAWK T100 (Tritium GTLS Self-illuminated)

    This is an update to the preceding review of the NITE HAWK. Since the release of the HAWK, NITE have subsequently produced a metal bracelet strap for it. The HAWK can be purchased with the metal strap instead of the rubber strap, or the strap can be purchased as an accessory for the HAWK.

    Time for a change:

    Personally, my preference is for metal straps, for their flexibility and ease of fitting and removing. The HAWK was not getting as much wrist time as it deserves main due to the strap, so it was time for a change and the new HAWK strap was ideal.

    Here it is with the original rubber strap.

    The last moments before the change.

    And it is off.

    The successor arrives.

    Taking a more detailed look:

    With its 24mm, the metal strap seems quite substantial at first considering the HAWK is a lightweight watch.

    The underside of the strap.

    A PVD stainless steel strap, with double locking deployment clasp.

    The clasp has the NITE logo engraved into it.

    The link pins are the push out type.

    The second lock is retained by rounded end spring pins, that keep it secure but allow the lock to be opened without difficulty.

    Fitting the strap

    If you are well versed in fitting and adjustment you might want to skip over this section and the next, but while I was fitting this strap I thought I would include some of the steps.

    With the rubber strap removed, the first end of the metal strap is fitted, ensuring it is the right way round. If you get it the wrong way round, putting on the watch becomes awkward.

    To easily fit the other side of the strap, it is best to split the strap in the middle by removing one of the spring bars in the clasp. You need a pin tool to push the end of the spring bar in.

    The other side of the strap is freed.

    It is now easy to fit the second end of the strap to the HAWK.

    An overall view of this.

    Adjusting the fit:

    The HAWK strap is generous in its full size, and as you can see here it is just a bit too big for me with all the links.

    Being a push-out pin strap, you need a tool to press out these tight fitting pins.

    I'm removing two links, having estimated this would be needed. When taking out links, if the number of links to be removed is an odd number, it is normal to take more out of the part of the strap that fits on the top side of your wrist (or as you look at the watch, the part of the strap fixed to the watch at 6 o'clock).

    To prevent damage to the clasp when pushing out the link pins, I tend to remove it entirely.

    In this case I've taken two from each side of the strap keeping it even.

    Much better fit! And of course the clasp has three fine tuning positions that the end of the strap can be set to.

    The HAWK sporting its new strap.

    What it is like in use:

    As I said earlier, I much prefer a metal strap, as it conforms to the wrist very comfortably, and is a synch to put on and take off without fiddling with a buckle.

    When the new strap arrived, my initial concern was that it was too heavy for such a lightweight watch. Actually I could not have been more wrong.

    The weight of the strap actually makes the HAWK very stable on the wrist, and the combination of the lightweight HAWK with the solid-link strap means the watch itself does not pull the strap round the wrist as can happen with heavier watches.

    The look is also quite different, taking it from a pure 'sports' watch look to a more refined casual watch.

    Though the rubber strap certainly has its place, I have found the HAWK transformed by the bracelet strap, and it is now getting much more wear.

    Yes, you can get cheaper generic metal straps, but the NITE HAWK strap has a quality feel to it and is worth getting. The feel is very different to a cheap strap (believe me as I did fit a cheap one, and there is no comparison), so is definitely worth getting the official strap. You get the quality and the NITE logo to match.

    If you enjoyed my reviews, please remember to 'Like' me on Facebook and follow me on Twitter @Subwoofer_CPF
    to get all the latest updates and news.

    You can also find exclusive insights on Instagram and Pinterest

    Tactical Reviews by Subwoofer
    Latest Reviews - @TacticalReviews and Facebook
    CandlePower Forums "Trusted Product Tester / Reviewer"

  3. #3
    Join Date
    Nov 2012

    Default Re: Watch Review: Nite HAWK T100 (Tritium GTLS Self-illuminated)

    Very nice watch and review.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts