Sunday, May 24, 2015

NITECORE SRT6 (1x18650)(Cree XM-L2)(930Lm) Magnetic Control Ring-Review

This is a review I wrote about a year ago,but had no time to post it in English.
Finally I can share it with you.

Nitecore SRT6 Night Officer is a flashlight from Nitecore's Smart Ring Tactical series lights.Flashlights with a regular rear switch for easy ON/OFF operation and magnetic control ring for gradually controlling brightness,selecting modes and ON/OFF(Standby),as well. The light is powered by single 18650 battery.Maximum brightness 930 lumens,minimum 0,1 lumen-according to the manufacturer.
All SRT flashlights have "tactical" oriented design and features-as crown bezel,easy access to Strobe mode,grip ring.Some of the models,except the reviewed below SRT6,have 5mm color LEDs for some more functionality-red light for night reading or green for hunting.Actually the 5mm LEDs are not powerful enough for using at long distance.The SRT6 without the extra color LEDs has less modes-less positions on the control ring,which makes it quicker and easier to use.
Anodizing in black color. Relatively glossy black. Very consistent anodizing-matched everywhere on the body.
The SRT6 has the typical for Nitecore precise knurling-,very helpful for the grip,pleasure for the eyes.
There are also some really nice grooves that make the grip even better.
Forward rear clicky switch.Momentary On is possible. Standard size switch cap with the letter N.
Easy access to the switch. Easy operation,too.
The grip ring is always useful addition.Unfortunately it is made of weak plastic.
No matter how careful the user will be,it's 99% sure that the ring will broke,even from itself.
My just broke in the hot time of the year. Probably,because of the different rate of expansion of the different materials-aluminum and plastic.(not yet broken on the pictures)
Deep aluminum reflector. Absolutely clean.Excellent reflective surface.
Cree XM-L2 T6 LED
17000cd peak beam intensity. Distance of throw 260 meters.
Ultra clear glass lens with anti-reflective coating-for maximum light transmittance.

Perfectly centered LED. The front end of the flashlight is very well done.
A closer look to the bezel.
Matte stainless steel crenelated bezel. Very precisely machined.Without sharp edges.
The control ring has limited track and can be rotated on 180°,not infinitely.

A lot of knurling and grooves for stable grip.
Excellent knurling-not too aggressive not too light,just the right(at least for my way of use).

Standard for Nitecore packaging. All important info printed on it.
Accessories-pocket clip,two spare O-rings,spare switch cap,lanyard.
In the box you will find also a warranty card and user manual.

The pocket clip can be attached in both directions. It seems sturdy,but is nothing special and I didn't use/test it much.It is used almost the same clip in all different size flashlights,which means it is not especially designed for heavy 18650 size flashlights.
The SRT6 comes with a nice,well made holster,but as you can see on the picture below,it seems designed for a smaller flashlight-maybe the Nitecore SRT3?

There is a state indicator at one of the sides-indicating Standby mode or low battery voltage.
Tail-standing is possible,but not quite stable.
Dimensions:
 Length: 153 mm
 Head diameter: 34 mm
 Body diameter: 25.4 mm
 Weight: 145gr (without batteries)


Can be powered by single 18650 Li-Ion battery or two CR123A.
Protected 18650 batteries fit well,which is really nice to see here. It's always recommended to use powerful flashlights with protected batteries.It's good to have this safety,especially for users with less knowledge about the Li-Ion batteries.
The SRT6 can be disassembled on three main parts.
Nice thick aluminum and overall very stable build.
All parts fit perfectly,without gaps in between.
As the most 18650 flashlights from last years,the SRT6 has two springs.One at the tail,one at the head.
The contact plastic board with a metal contact point,acts as a reverse polarity protection(protects the flashlight from damage if the battery is inserted in reversed position).
The existence of this type mechanical protection,makes using flat top batteries impossible.
Two spring design makes the flashlight suitable for a gun mount,too.The springs should reduce the stress over the battery while shooting with the gun.
A good closer look at the grip ring-my is already broken and I think over how to make a new one from a better material.
Rectangular cut threads at the head end. Triangular cut threads at the tail,anodized,too.
Excellent machining. Absolutely clean threads.
Even closer look.
With a protected battery inserted in the tube.

Using the SRT6 is easy and convenient.
The tail switch disconnects the power physically. Can be used for momentary activation-for signaling,etc.
By twisting the control ring,we can adjust the brightness infinitely from from really slight glowing to maximum brightness. Twisting clockwise increases the brightness,twisting counterclockwise decreases it.
No defined brightness modes. We choose the brightness from 0.1 to 900 Lm.
Rotating the ring more to the left after minimum brightness,puts the light into Standby mode-no light from the main LED.Only the side indicator light blinks to indicate Standby state.

There are two flashing modes,too. They are placed at the ends.Twisting to the far right position,activates Strobe mode. At far left is the SOS mode.
There are dents(no visible marking,but can be felt while twisting the ring) for OFF(Standby) and Max brightness. Strobe mode is next after the dent for Max brightness. SOS is next on left,after the Off/Standby dent.
This layout allows quickly switching to Strobe mode,while using the light on max output.
Thanks to the combination of two different type switches,the mode can be selected even while the light is deactivated-for example you can choose the brightness level before activating the light,or to choose Strobe to be ready for use when needed.

Short video presenting the SRT6's design and handling.
No voice.Turn on annotations for some text info.


Below is a runtime graph-showing the Lumen output in percentage through the time,in minutes.
Battery Keeppower 3400.
The Nitecore SRT6 is decreasing the output two times during the first 20 minutes.
The purpose of these timed Step-down actions is to protect the flashlight from overheating and maybe the battery from the high continuous discharge..
First step-down is 5 minutes after activation.
The second step-down is 15 minutes after the first.
After that the light output continuous until the battery lasts.
When the battery is fully discharged the side indicator blinks quickly to tell us that is time to replace/recharge the battery.
A decent performance.The 5 minutes period and following step-down is quite common performance for this size powerful flashlights,so we can't expect much more from this flashlight.
The light has no visible PWM flickering or hearable noise.

The light from the Cree XM-L2 LED is cool white,without greenish or bluish tint.
Quality white light.
Normal beam,not too narrow,not too wide. Suitable for different situations. 17000cd peak beam intensity.
930Lm max brightness according to Nitecore. I measured about 780 Lumens(Ansi)



5 meters,1/6sec



 5 meters, 1/50sec



Outdoor Beamshots







Closer distance




ThruNite TN12, Olight M22, XTAR B20, Klarus ST11, Eagletac T25C2, Nitecore SRT6


As any other flashlight and actually any product,the Nitecore SRT6 has its good points,but also its bad points. I can't really find many bad points,so far and this makes the SRT6 one of my favorite flashlights.
The aluminum parts are machined with care to detail,perfectly anodized-not something new for Nitecore.
The size is a little bigger than the other competing flashlights,but in hand this gives comfortable grip-for example the Olight M22 warrior is impressively short for its performance,but I feel it too short for comfortable grip.Part of my palm holds over the anti-roll ring-not very comfortable place to hold.
In terms of lighting performance,the SRT6 performs more than well.
No distracting PWM. No unsuitable,defined modes. The brightness level can be adjusted according to the actual situation/needs,from really low,to absolutely acceptable,even for an old model lumen output.

The combination of control ring and conventional rear switch,gives even more freedom in use.
Thanks to the rear switch you can use the SRT6 as a single mode flashlight.Just use the brightness,or Strobe from the control ring,then just push the tail switch for ON/OFF without worrying for mode memory and other that can turn the UI in something unusable.
You can also leave the tail switch ON,then just use the control ring to turn the light on and to adjust brightness.
About the user interface-I have not much what to complain. The SOS mode is probably the least used mode
and many users will find it needless,just overloading the UI a little. It's hard to activate it accidentally,but yet, it's still there.
The only disappointment for me is the grip ring-made of plastic and guaranteed to crack,even from itself.
I rely on the grip ring for best possible grip when using the flashlight and really like to have it there.
I will probably glue the ring or make a new one,but this is not something the user should be loaded to do and not everyone can/have time to do it.
My test/review sample of the SRT6 is more than a year old. The grip ring may have been redesigned,but I have no any information about that. If the grip ring is important feature for you,be sure to ask the dealer about it,before buying the SRT6 .

Thanks for visiting my review blog!
Feel free to send me any questions or comments.