Review: NITECORE TM16 (4x18650)

The latest member of the Tiny Monster family, the TM16 is designed as a high power, extended range, compact search light.





Taking a more detailed look:


Standard NITECORE TM series packaging is used.




A closed-cell foam liner is used.




The TM16 comes with spare O-rings, instructions, a lanyard and a thin cord (which I believe is used to assist in fitting the lanyard through a hole in the tail-cap).




The TM16.




Taking our first look into that compound reflector.




There are a set of cooling fins machined into the base of the TM16's head.




Looking from the rear of theTM16.




In the tail-cap there is a threaded socket for a standard tripod screw.




For a multi-emitter light the individual reflectors are relatively deep.




Using the same system employed in several NITECORE lights, the TM16 has a rotating PCB in the tail-cap with two locator pins.





Tapezoid threads are used.




The contacts inside the battery tube.




Here you can see the cell tubes and the locator pin holes. You can also see the cell polarity labels.




Looking straight into the compound reflector at the four XM-L2 LEDs.




Another view of the reflector.




And a closer look at one LED.




Connecting the TM16 to a tripod using the threaded hole in the tail-cap.




Putting the TM16 next to the Fenix TK75, you can see how the TM16's body is smaller thanks to not having a battery carrier.




The TM16's head is slightly bigger to better house the fourth LED, but still remains a very manageable size.




The TM16 with the four cells it uses.




Cells loaded and ready to go.




On its lowest mode 'Lower', if you look closely at the LEDs you can see the XM-L2's distinctive pattern of dots.





The beam

Please be careful not to judge tint based on images you see on a computer screen. Unless properly calibrated, the screen itself will change the perceived tint.
The indoor beamshot is intended to give an idea of the beam shape/quality rather than tint. All beamshots are taken using daylight white balance. The woodwork (stairs and skirting) are painted Farrow & Ball "Off-White", and the walls are a light sandy colour called 'String' again by Farrow & Ball. I don't actually have a 'white wall' in the house to use for this, and the wife won't have one!


Starting indoors, as expected with a compound reflector, the spill is flower shaped, but the hotspot is well formed.




To properly show the power of the TM16's beam first we look at my reference Fenix TK41.




And then the TM16!





Modes and User Interface:

The TM16 has a total of five constant modes (Turbo, High, Medium, Low, Lower) and three flashing modes (Strobe, Beacon and SOS). Like many other NITECORE lights this is controlled by a dual button.

From OFF, to switch ON to the last used steady white output, briefly press the Power switch. When ON, press the Mode switch to cycle through Turbo -> Lower -> Low -> Mid -> High back to Turbo etc. To switch OFF briefly press the Power switch.

From OFF, for direct access to Lower, press and hold the Power switch for more than 1s.

From OFF, for direct access to Turbo, press and hold the Mode switch for more than 1s.

To access White flashing modes, from ON, press and hold the Mode switch for more than 1s. This will activate strobe. Press and hold the Mode switch for more than 1s again to switch to Beacon mode. Press and hold the Mode switch for more than 1s once more to activate SOS.
Once activated, pressing the mode switch briefly returns the TM16 to the previous steady mode, or a brief press of the Power switch will turn the TM16 OFF.

There is a 'Standby' mode which uses brief low power flashes of the blue switch indicator LED to act as a locator to allow you to find the TM16 in complete darkness. To activate Standby, from ON press and hold the power switch for 3s until the blue switch light comes on. Although low power, the flashes are bright enough to disturb someone's sleep. Exiting standby mode is achieved by switching on the TM16.

There is a lockout mode included. With the TM16 ON, press and hold both buttons simultaneously for 1s to enter lockout. When entering Lockout, the TM16 will turn off and give a brief flash of the main beam as you release the buttons. Like this the buttons will not turn the TM16 on. Thanks to the button design this can be done easily with the thumb. To exit Lockout press and hold both buttons simultaneously for 1s and the TM16 will turn ON in the last used mode.

Lastly when first inserting cell/s into the TM16 or briefly pressing the mode switch when OFF, the blue switch light will flash to indicate the battery voltage to 0.1V. During normal use, you can get an ideal of the charge level by pressing the mode switch from OFF and the TM16 will flashes once, twice, or three times. Three flashes indicates full power.



Batteries and output:

The runs on only 4x 18650.

To measure actual output, I built an integrating sphere. See here for more detail. The sensor registers visible light only (so Infra-Red and Ultra-Violet will not be measured).

Please note, all quoted lumen figures are from a DIY integrating sphere, and according to ANSI standards. Although every effort is made to give as accurate a result as possible, they should be taken as an estimate only. The results can be used to compare outputs in this review and others I have published.


* Beacon and Strobe output measurements are only estimates as the brief flashes make it difficult to capture the actual output value.

Peak Beam intensity measured 114000lx @1m giving a beam range of 675m.

There is parasitic drain. As with some other NITECORE 4x18650 lights, the drain is not the same for both pairs.

Drain for Pair A (closest to the switch) is 131uA. This drain would fully deplete the cells in 2.96 years.
Drain for Pair B is 70uA. This drain would fully deplete the cells in 5.54 years.

To completely stop the drain the tail-cap must be almost fully removed, so it would be better to remove the cells if the TM16 is used as a standby light for more than a few months.


There was no timed step down during the output test and there was also no drop to a lower level with the TM16 instead taking as much as it could from the cells.





Troubleshooting

This is a new section I am adding to mention any minor niggles I came across during testing, in case the information helps anyone else.

No issues were encountered during testing.

As per the description of this section, this information is provided in case anyone else finds a similar 'issue' that might be fixed in the same way.



The TM16 in use

I wanted to start by addressing something I heard about, as it is a potential safety concern, but I have not been able to replicate this.

It has been reported elsewhere that with all 4 cells fitted, it is possible to misalign the locator pins and put them into the battery tube (instead of the locator sockets), and still be able to screw the tail-cap on. If this happens you will push the pins into the bottom of two cells damaging them badly. However I have tried to do this, and when the pins are misaligned, the threads do not catch and start. Perhaps with shorter cells this might be possible, but I could not recreate this.


Moving onto the TM16 in real use:

There is a definite benefit in the battery tube design allowing it to be narrower than many other 4x18650 lights. Size and balance make it comfortable to hold.

You need to be careful inserting the cells as the top of each cell channel has a sharp enough corner to damage the cell wrap.

Side switches are generally the most comfortable to use (unless your requirement is for an over-hand tactical grip) making the TM16 very ergonomic to use. The dual button switch works very well, right up to the point you put gloves on. Unlike NITECORE's EC4 which has a raised ridge between the buttons that gives tactile feedback even with gloves on, the TM16's two buttons are not separated like this. A pity as this simple change would make a big difference.

The easy direct access (without gloves) to Lower and Turbo is a great feature of the NITECORE dual button interface.

As well as its ultimate high power output, the TM16 has a very useful 'Lower' mode at 5lm. This is often left out of high power lights, but is a really important addition.

Though I've yet to use it practically, I'm glad to have the ability to tripod mount the TM16, as it allows you to use the TM16 as a fixed task light.




And the TM16 where it counts, outside at longer ranges. Despite its compound reflector, the TM16 manages to push some serious lux out. Though not brilliantly shown in this photo, the distant tree (approx. 300m) is lit up in the TM16's hotspot.





In this photo a closer tree (approx. 100m) is lit up and the telegraph pole in front of it shines brightly.




The TM16 gives you power and range in a relatively compact light.



Review Summary

reserved for updates...

Please feel free to ask questions, give feedback or comments.

Excellent review and beamshots.
Just want to add that when first inserting the cells and tightening the cap, the blue LED underneath the switch will flash to indicate the remaining voltage, for eg. to indicate the battery voltage is 4.2V, it will blink 4 times quickly,paused for a while and then blink another 2 times.

Main review updated to include comment about potential cell wrap damage due to sharp corners on the cell channels.

akhyar said:

Excellent review and beamshots.
Just want to add that when first inserting the cells and tightening the cap, the blue LED underneath the switch will flash to indicate the remaining voltage, for eg. to indicate the battery voltage is 4.2V, it will blink 4 times quickly,paused for a while and then blink another 2 times.

Click to expand...

It is odd that the TM16 has this mixed power indication. In other models you generally either get the actual battery voltage on first inserting cells or a power check, or you get the 1, 2, 3 flash method, but the TM16 uses both. Although having just said that it does make sense that the detailed voltage is not always shown as if you are waiting for one set of flashes then another set of flashes to get the full voltage it is much quicker to get 1, 2 or 3 flashes for a general idea of the power left.

Just as an FYI, eBay sells a holster from hkequipment that fits the TM16 very nicely. It is an Acebeam holster, and the last time I checked it was $16 USD with free shipping. I would class it at the same quality and design as the holsters Nitecore includes with its other lights.

Great review subwoofer. And your pictures really shows that details of the light. Thanks for sharing! :twothumbs

I'm blown away by the large number of high-quality reviews you have turned out in the past month.

Many thanks!

Subwoofer,

What is the debris on the rear of the light as shown in this picture?

The picture before, I thought that you may have had the light outside in a slight rain, but after seeing the second image, I decided to ask.

Secondly, the 2015 Fenix catalog no longer lists the TK41 light. Are you planning on continuing to use the TK41 are are you going to make a change? I love my TK41's, both the 860 and 900 lumen versions.

Finally, you indicated that the switch that Nitecore is using is somewhat recessed. Are the clicks from mode to mode loud or are they muted?

Good, solid review, up to your usual standards. I like that you included the longer range beam shots since this is supposed to be a searchlight.

Two nits. First, when replacing the tail cap and powering up, the voltage reading I got was 4.1, which tells me that the driver circuit must be averaging the voltages to get a representative reading. Also, when I tapped the Mode switch immediately after powering up and/or anytime the light was off, what I got was the three blink general reading.

Also, when the light is off, pressing the Mode switch twice rapidly will go direct to Strobe. When one enters Strobe mode this way, one cannot move on to SOS or Beacon, only back to regular mode.

I find it interesting that the manual states 18650 only, but the decals on the battery tubes state 1 18650 or 2 CR123. Hope no one blows their driver by trying to use CR123s!

would like to see a head-to-head shootout between the Nite core TM 16 and Fenix tk75 4000 lumen model .would be interesting !!

KeepingItLight said:

I'm blown away by the large number of high-quality reviews you have turn out in the past month.

Many thanks!

Click to expand...

Thanks for saying so

I'll give you a little insight into my review process:

Currently I'm in what I call my 'harvest period' so I'm putting out more reviews than the overall average rate. This is due to working in batches to improve my efficiency.

For entire batch each stage is completed -
Initial photography (packaging, product details all in as new condition)

Technical testing, measurements and runtime traces
User feedback/testing period (minimum of 2 weeks using the product every day)
Beamshot photography
10m lux measurements
In-the-field photography
Photo post processing, animation preparations, uploading to host
- then the 'Harvest Period'
Review copy writing
Publishing and final proof reading

This process has to fit around a full time job, a wife and a backlog of home repairs. I've also lost 6 weeks due to medical reasons so am behind where I should be.

NoNotAgain said:

Subwoofer,

What is the debris on the rear of the light as shown in this picture?

The picture before, I thought that you may have had the light outside in a slight rain, but after seeing the second image, I decided to ask.

Secondly, the 2015 Fenix catalog no longer lists the TK41 light. Are you planning on continuing to use the TK41 are are you going to make a change? I love my TK41's, both the 860 and 900 lumen versions.

Finally, you indicated that the switch that Nitecore is using is somewhat recessed. Are the clicks from mode to mode loud or are they muted?

Click to expand...

The debris is a combination of lubricant and dust. Unless otherwise stated all detailed photographs are fresh-out-of-the-box so exactly as you would have found it if you had bought this particular light.

The outdoor photos might show a hint of mist. It was not raining but definitely had moisture in the air.

Good question about the TK41. It has been a regular reference light and at around 800lm is a nice comparison light as it is neither too bright or too dim, and is super consistent as well. Currently no plan to stop using it when I want to make that type of comparison, but I'll keep an open mind.

No, the switch on the TM16 is not recessed. The buttons are slightly raised but with no tactile separator (like the EC4 has - see NITECORE EC4 979lm (2x18650, 4xR/CR123)) The clicks are slightly muted.

Timothybil said:

Good, solid review, up to your usual standards. I like that you included the longer range beam shots since this is supposed to be a searchlight.

Two nits. First, when replacing the tail cap and powering up, the voltage reading I got was 4.1, which tells me that the driver circuit must be averaging the voltages to get a representative reading. Also, when I tapped the Mode switch immediately after powering up and/or anytime the light was off, what I got was the three blink general reading.

Also, when the light is off, pressing the Mode switch twice rapidly will go direct to Strobe. When one enters Strobe mode this way, one cannot move on to SOS or Beacon, only back to regular mode.

I find it interesting that the manual states 18650 only, but the decals on the battery tubes state 1 18650 or 2 CR123. Hope no one blows their driver by trying to use CR123s!

Click to expand...

It is not good that the manual and graphics in the battery tube disagree on using CR123. My suspicion is that you could use CR123 perfectly well as long as you don't leave it on Turbo for long.

I've come to a conclusion that really 700lm per 2xCR123 is the safe limit for these cells. That would translate to 2800lm for 8xCR123 and the TM16 will be pushing 3600lm+ on Turbo. So I think it would 'work' on CR123, but not be safe if using Turbo. This is an opinion only and is NOT tested.

subwoofer said:

I've come to a conclusion that really 700lm per 2xCR123 is the safe limit for these cells. That would translate to 2800lm for 8xCR123 and the TM16 will be pushing 3600lm+ on Turbo. So I think it would 'work' on CR123, but not be safe if using Turbo. This is an opinion only and is NOT tested.

Click to expand...

As you know from our exchanges this week, I too am concerned about excessive current discharges from CR123A batteries. Most are rated for a maximum continuous discharge of 1.5A. Unless that is a meaningless specification, we may be at the point where LED flashlights have outgrown this battery.

At present, we are relying on the good sense of a flashlight's owner in order to keep current discharges within the 1.5A limit. That's a system that's guaranteed to fail. It would be better if a flashlight could detect the presence of CR123A batteries, and limit current automatically.

KeepingItLight said:

we may be at the point where LED flashlights have outgrown this battery.

Click to expand...

We are already, and have been for a couple of years. CR123 still has a place, but in the right lights and the right situations.

KeepingItLight said:

At present, we are relying on the good sense of a flashlight's owner in order to keep current discharges within the 1.5A limit. That's a system that's guaranteed to fail. It would be better if a flashlight could detect the presence of CR123A batteries, and limit current automatically.

Click to expand...

Unfortunately yes, we are now relying on the built-in safety features of the cells and users common sense to read and follow the instructions.

I suspect it will take a nasty incident before any changes are made to the lights to prevent use of the wrong cells. It is much easier for the manufacturer to say "do not use CR123" than to protect against them being used, so this is what they will do.

Most AA lights are not designed to protect against the user inserting 14500 cells, so why should a manufacturer build in protection for users inserting the wrong type of cell when they say not to use CR123?

There are many lights now saying 18650 only, and I think that realistically, considering the cost of CR123s, most users are only going to want to use rechargeable cells anyway. People willing to spend the money on CR123s will hopefully understand their limitations better.

Vinh's lights all come with the warning that "IMR cells only" are to be used. I'm sure someone with one of his lights has put normal li-ions in them at some point. Many high output light manufacturers are now stating li-ion only, and some recommend IMRs.

I agree with you raising awareness of this potential issue, but think this is more of an education matter than design issue.

subwoofer said:

We are already, and have been for a couple of years. CR123 still has a place, but in the right lights and the right situations.

Click to expand...

This is a good point. I almost amended my OP to say something like this. A conservative design that does not draw more than 1.5A from its CR123A batteries is obviously fine. I was thinking about the recent Fenix E20 2015 Edition. That's a 2xAA model that does nothing fancy. A analogous CR123A design would keep amperage down to safe levels.

subwoofer said:

Unfortunately yes, we are now relying on the built-in safety features of the cells and users common sense to read and follow the instructions.

I suspect it will take a nasty incident before any changes are made to the lights to prevent use of the wrong cells. It is much easier for the manufacturer to say "do not use CR123" than to protect against them being used, so this is what they will do.

Click to expand...

I was thinking about flashlights that are rated for CR123A batteries, but then draw more than 1.5A from them on high and turbo. At present, the instructions for these flashlights rarely, if ever, warn against pulling too many amps on high. Telling a user that it's okay to use CR123A, and omitting even the mildest warning, guarantees that many owners will run those batteries at excessive current levels.

subwoofer said:

Most AA lights are not designed to protect against the user inserting 14500 cells, so why should a manufacturer build in protection for users inserting the wrong type of cell when they say not to use CR123?

Click to expand...

I meant only to suggest that those flashlights that are approved for CR123A should have circuits that limit current levels when that battery is used. Trusting every user to remember or care that certain modes are verboten for CR123A is not a realistic expectation.

If a certain battery is "banned," then I agree, there is no need to design circuits to protect against that battery being used.

subwoofer said:

I agree with you raising awareness of this potential issue, but think this is more of an education matter than design issue.

Click to expand...

That's why I appreciate you speaking out on the issue. Any review for a flashlight that is approved for CR123A should include a discussion of current demands on high output modes. If there is a likelihood of drawing more than 1.5A, a review should say so.

I, for one, would love to see measurements of the current drawn from CR123A batteries. For other chemistries, I don't think that is necessary, but with CR123A, many flashlights are pulling more amps than the battery is rated for. I think it is worth measuring in order to determine the modes and flashlights that do that.

I'm glad to read I am not the only one who worries about demanding too much from primaries. I use my sc32w with imr even though I had purchased it explicitly for use with single primary because current draw is too high with primary. Ironically it draws less from li ion batteries.