Another luxury purchase. Still on the search for perfection, Three Points of the Compass splashes out on yet another thermometer. Will this prove to be ‘the one’?

Three Points of the Compass has carried a thermometer on trail for over forty years. A couple of little traditional glass gauges sufficed for much of that time. Usually attached to a zipper pull, the first was the type of thing that comes out of a cracker, in fact it may very well have come from a cracker. An equally small Silva thermometer replaced it. Each was remarkable not only for never breaking, but also for how inaccurate and difficult to read they were.

I stepped things up a little when I purchased a Brunton Nomad G3 Pro ABC. I carried that robust instrument for thousands of miles and really wanted to like it. However I always struggled with the user interface. It was so complicated. I would spend an hour every so often refamilarising with how to set and read it, then promptly forgot over the next few days. Don’t get me wrong. The Brunton could do a great many things that I am sure many hikers and backpackers might like. It was simply that it did too much. All I ever really wanted was the time and temperature. Altitude readings (barometric pressure) are uncertain anyway unless the instrument is constantly re-calibrated, I didn’t need a digital compass and I rarely required an alarm. Not only that, it was also quite large and at 39g, while not ridiculously heavy, it was no lightweight either. These are the same factors that have dissuaded me from buying a smartwatch for many hundreds of pounds. I simply don’t want or need most of the features found on these.

My phone has largely replaced any need of a watch or alarm and I haven’t worn a watch on my wrist for over three years. All I really want is a thermometer. Not an essential I know, but I do like to know what temperature it climbed to during the day and what it dipped to at night. Regular readers will be aware that I purchased an Oria SensorBlue Keychain Thermometer Hygrometer earlier this year. I wanted to like it, but even that little instrument does far more than I want and I have not been enjoying using it or having to use an app on my phone to access the data. The SensorBlue may suit many a user and I am sure there are a great many people who will find the data gathering and user interface exactly what they want, just not me.

Gear talk: the Oria SensorBlue Thermometer Hygrometer

One of the comments to my initial review of the SensorBlue suggested a popular alternative that I had already considered, and had been hankering after for quite some time, but had been put off due to the cost of purchasing one in the UK. ‘Buy once, cry once’ is good advice, but I failed to follow it. Earlier this year I swallowed hard and hit the buy button. This was for a Chinese made product, that is designed and retailed by a US company and is not readily available in the UK. My latest, and hopefully last, thermometer cost me £30, plus tax, plus shipping, a total of £42. A shocking amount for a limited use, luxury item I know. Compare this to the total cost of £10.19 for the SensorBlue, and my new thermometer has far less functionality!

However, the ThermoWorks ThermoDrop delivers exactly what I want. It is small, light, is easy to operate and quick and easy to read. It shows temperature readings in either Celsius or Fahrenheit and, more importantly, is accurate. There are a couple of unobtrusive extra features too, I’ll get to them. The only real downside for me was the cost of this simple gadget.

It came in plastic and card packaging, together with a slip of paper with the operating instructions and, more importantly, a certificate of calibration. I have subsequently checked it against a couple of household instruments I have and these suggest that middling temperature readings remain accurate. Certainly an ice-bath test shows a 0°C (32°F) reading is accurate. Available in a wide range of ten colours, I chose black as I want it reasonably unobtrusive if left hanging from a pack left unattended outside a shop or on a luggage rack on a train or bus. The ThermoDrop has a hard plastic case with a hard rubber outer edge to aid grip. There is a single button and a single hole at the end to attach it to whatever you wish to. While the ThermoDrop came with a split ring, I almost immediately discarded this as I prefer it hanging from my pack via a more easily detached micro-lock s-biner from Nite Ize. It measures 49mm x 33 mm x 12.5mm and is advertised as weighing 14.3 grams. This is the weight repeated by just about every reviewer or owner of these thermometers though I suspect this is based on the usual manufacture massaging of stats. On my accurate digital scales, mine, with no attachment ring at all and with battery, weighs 14.55g. Fractions of a gram maybe but we are talking about accuracy here. With an additional mini-biner as shown, it totals 18.5g.

I like that the display auto-orientates, or, more accurately, flips. Hold it one way and the readout can be seen and read, tip it upside down, and the display flips to the right way up. This feature simply adds to how user friendly this little instrument is. The digital display has a back light if required for reading at night or in poor light.

The ThermoDrop has joined me on a minority of trails so far this year as I have been using the SensorBlue until I rejected this in favour of my latest greatest purchase, however it has done a handful of local walks and also travelled overseas with me and confirmed the silly temperatures the Canary Islands experienced recently. Having exceeded 50°C , the reading changed to HHH, which I can only presume means HOT HOT HOT! At the other end of the scale, when it drops below it’s range, it then registers LLL.

Operating range is -13°F to 122°F (-25°C to 50°C) and accuracy should be +/- 1.8°F (+/- 1°C) over the full range. It is powered by a tiny CR2025 battery, giving a purported 4000 hour life (166 days). Weatherproofness is IP67, which is pretty good, being both dust tight and capable of being immersed in a metre of water for up to 30 minutes. I am unlikely to be doing that, but this should mean that it will withstand any amount of rain being thrown at it. It has a two-year warranty.

The digital reading is simple and fairly large within the confines of the small screen. The instrument also has a maximum/minimum reading, accessed by pressing and holding the single button for three seconds. This shows a maximum reading, pressing again reveals the minimum reading. Powering off the instrument and restarting resets the max/min. Recording the overnight minimum temperature is a handy feature. While it is designed to stay on permanently so as to record max/min temperatures it can be turned off if wished.

Pressing the single button once, operates the backlight for 10 seconds. Something I can see me frequently using this winter during the long cold nights. On trail at night I usually relocate a thermometer from the pack’s shoulder strap or zipper on my chest pouch to the door zipper pull on my shelter’s bug netting.

There are a couple of potential issues with the ThermoDrop. It does not deliver an instant reading of temperature, it records ambient temperature and does take a few minutes to register changes in temperature. It doesn’t handle radiant heat at all well, it isn’t intended to. Place this in direct sun and it will register the temperature of the plastic case, which will be higher than the surrounding air, particularly if it has a black case, like mine. That doesn’t trouble me as I need it to show the temperature over an extended period and it would normally be hanging from the pack, moving in and out of shade, when it will deliver a more accurate reading. Hanging inside a tent overnight is even more accurate of conditions. There are other products out there if you want to record instant changes in temperature. You also have to be careful to hold it by its hanger as it will pick up the temperature of your hand. Some users may find the low temperature reading capability insufficient for them. A low of -13°F / -25°C is fine for me, though perhaps not for others. Finally, there is the cost, especially for a UK based hiker wanting to purchase this. I’ll try and remember to report back on how I get on with the ThermoDrop long-term.