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Nitecore has long been on the cutting edge of flashlight technology, and they're not slacking off now. As one of the first to adopt magnetic control ring technology, they're exploring it's capabilities with their new SRT series. The SRT series lights use the control ring not only for infinite variability, but for various utility modes and control of multi-color emitters. This review covers the smallest of the SRT's, the SRT3 Defender, powered by a single 16340 or 14500 sized battery, utilizing a Cree XM-L2 and a single small red/blue emitter.
Thanks to Nitecore for providing the SRT3 for review.
I'll be reviewing the SRT3 in two sections: first, I'll discuss the light objectively (the facts about the light itself), then I'll discuss the light subjectively (my impressions about the light's performance when used for specific applications). If you have any other specific applications you'd like the light tested for, let me know and I'll see what I can do.
Video Review
Below is a video review of the SRT3. Due to my old image hosting site closing down, I've got new restrictions on image uploads and have replaced the "Construction" section of my reviews with a more detailed video review.
This video is available in 1080p HD, but defaults to a lower quality. To select the playback quality click the settings button (looks like a gear) after you've started the video.
Objective
Manufacturer's Specifications
Price: 90 USD
Dimensions
User Interface
The interface of the SRT3 has many options, but is incredibly intuitive. To turn the light on/off, you use the tail switch at the rear (half-press for momentary on or full press for constant on), and to control the output you use the control ring.
With the light pointing away from you, turning the ring all the way to the left will start you in the Beacon mode, steady quick bright flash at low frequency. Turning right, you next get the SOS mode, then a Red/Blue Strobe, then Blue, then Red, then the Minimum White output, then a smooth Infinitely Variable transition up to the Maximum White output, then a high-frequency Strobe. Each of these positions has a detent in the control ring so it feels like a soft "click" into position, providing tactile feedback and prevent the ring from changing position in you pocket. The exception is the Infinitely Variable section, which has a detent on either end for the Min and Max output, but is smooth in between.
Action Shots
You can click on any of these shots to see them full size.
Light in Hand (without and with AA extender)
White Wall (Low, Medium, High, Blue, Red)
ISO 100, f/3.3, 1/20"
(Blue and Red at 2")
BeamSlice
MugShot
Indoor Shots (Low, Medium, High, Blue, Red)
ISO 100, f/3.3, 1"
(Blue and Red at 10")
Outdoor Shots (Low, Medium, High, Blue, Red)
ISO 100, f/3.3, 2.5"
Long-Range Shots (High)
ISO 100, f/3.3, 5"
Performance
Submersion: I submersed the SRT3 under a foot of water for an hour, using the switch and control ring during that time, and found no evidence of water damaging or entering the light.
Heat: The SRT3 doesn't display any significant heat buildup.
PWM:
Drop: I dropped the SRT3 on various surfaces (carpet, grass, packed dirt, hard wood) and it did not suffer any cosmetic or functional damage.
Reverse Polarity Protection: The SRT3 uses mechanical reverse polarity protection to prevent the negative terminal of a battery from making electrical connection with the head.
Over-Discharge Protection: The SRT3 does turn itself off before over-discharging a lion, but as always, I recommend recharging the battery before this is necessary. The output of the SRT3 drops slightly before it's about to turn off, so that's your cue.
Spectral Analysis
All light that we see as white is actually made up of several different colors put together. The relative intensities of the different colors in the mix are what determine the tint of the white we see. For example, cool white LED's have a lot of blue, and warm white LED's have more red or yellow. This measurement was done on a home made spectrometer. The plot below the picture is corrected for the spectral sensitivity of the human eye. Note: the peak in the 900nm region doesn't really exist, it's a piece of the second-order spectrum that's showing up here because of the high intensity of the light source.
Output and Runtime
ANSI FL-1 runtime ratings are the time it takes for a light to fall to 10% of it's original output (counting from 30 seconds after turning the light on).
The vertical axis of the graphs below represents a relative brightness measurement using a home made light box. The horizontal axis is time in hours:minutes:seconds. Runtimes are stated in hours:minutes:seconds. These graphs may be truncated to show detail.
Mode Comparison
Max
Medium
Throwing Distance
ANSI FL-1 standard for stating a light's throwing distance is the distance at which the peak beam intensity (usually at the center of the beam) is 0.25 lux. I calculate throwing distance and candela (lux at 1 meter) by measuring peak beam intensity at five different distances and using the formula lux*distance^2=constant.
Peak Beam Intensity: 4532cd
Throw Distance: 135
(As a side note, Nitecore's claims are only 32cd off from what I measured, which is an impressive 0.7% error :thumbsup: )
Subjective Review
Quick break down:
+ Multi color option
+ Infinitely variable
+ AA extender included
+ High max brightness
+ Low min brightness
+ Very good regulation
+ Magnetic control ring
+ Indentations for modes
+ Perfect size for larger hands
+ Firm, screw-on clip
- A bit larger than some might EDC
I'll start by saying this light has replaced the SWM V11 as my new general purpose EDC, a position that was previously held by the SWM V10. This is a hard spot to get into, but the SRT3 has been nothing short of excellent.
My favorite aspect of this light has been the implementation of the magnetic control ring. So far, I've found the magnetic control ring to be the most practical and useful sort of user interface on a multi-mode flashlight for most uses. There are certainly a few uses where a standard switch is preferable, but for general use the magnetic control ring is incredibly intuitive and simple. For my mind at least, it helps to associate the modes with some physical position, instead of just some electronic setting--I know "where the mode is", not just a pattern of switching I have to follow to make it happen. On the SRT3 in particular, the magnetic control ring has been used very effectively. Each mode has it's own position on the control ring, and detents give some satisfying feedback to let you know when it's in the spot for the next mode and help to keep it from sliding out of that position accidentally. The infinitely variable portion of the ring has a detent at the max and min position, but a smooth travel over the intermediate settings so you can get the level you want. The max brightness is about 200 lumens for a AA, and up to around 650 when you use lithium ion batteries, and I've found even 200 lumens is plenty for most short to mid-range tasks in the dark. The minimum brightness is very low--lower than my SWM V10's or V11's, but not quite as low as my EYE10 TIC (which literally fades away into imperceptibility). I find the min is plenty low for reading something without destroying night vision or navigating a dark house without disturbing sleepers.
So far, I haven't found too much use for the red and blue modes other than to entertain my children, but for me that is a significant thing. I know that many people say the red and blue have certain tasks they are especially useful for in low light conditions, but I haven't had the opportunity to use them it those ways, so I won't comment on it at this point.
Taking a look at the output graphs above, you can see that the SRT3 has very good regulation, which is not really the norm for infinitely variable lights. Something about the electronics required for infinitely variable output seem to make regulation of that output harder, but Nitecore has done a good job here of combatting that effect. Also, you can see the regulation holds pretty well for both NiMH and Li-Ion batteries, which is uncommon.
I also want to point out the clip on this light. Many lights this size have a clip, but few of them make me feel confident that the light is secure in my pocket. This clip is held down by two screws, so it's not just a clip-on-clip that will fall off easily. It's also made of a metal that gives a firm hold without being too difficult to manipulate. This seems like a little thing, but it can make a big difference.
It's also worth noting that the AA extender is included with the light, so you don't have to buy a separate accessory. This is a nice touch, and adds a great deal of functionality. With some extenders I've used there can be trouble with the electrical connection when the extender is in place, but I haven't experienced that here.
The one possible drawback here is the size. The SRT3 is significantly larger than other lights in the single AA or single 16340 classes. It's got an excuse, with the magnetic control ring plus electronics for control of multiple emitters, but this still may be an issue for some. I find it has no trouble settling comfortably into my pocket, and the size is actually just right for my larger-than-average hands, but I can see for some people that it might be a bit larger than ideal.
So, the SRT3 is an all-together excellent general purpose light. I would not hesitate to recommend it to anyone looking for a EDCable single cell light. The magnetic control ring ensures that the multiple modes are not confusing or annoying but only very useful, the construction is on-par with Nitecore high quality, and the large size for its class is not any real hindrance to its use.
Long Term Impressions
I'll fill this part in after carrying the light for a while. If nothing get's added here, either I find nothing else worth noting about the light, or I end up not using it often.
Don't forget to click "Like" after the page loads!
Nitecore has long been on the cutting edge of flashlight technology, and they're not slacking off now. As one of the first to adopt magnetic control ring technology, they're exploring it's capabilities with their new SRT series. The SRT series lights use the control ring not only for infinite variability, but for various utility modes and control of multi-color emitters. This review covers the smallest of the SRT's, the SRT3 Defender, powered by a single 16340 or 14500 sized battery, utilizing a Cree XM-L2 and a single small red/blue emitter.
Thanks to Nitecore for providing the SRT3 for review.
I'll be reviewing the SRT3 in two sections: first, I'll discuss the light objectively (the facts about the light itself), then I'll discuss the light subjectively (my impressions about the light's performance when used for specific applications). If you have any other specific applications you'd like the light tested for, let me know and I'll see what I can do.
Video Review
Below is a video review of the SRT3. Due to my old image hosting site closing down, I've got new restrictions on image uploads and have replaced the "Construction" section of my reviews with a more detailed video review.
This video is available in 1080p HD, but defaults to a lower quality. To select the playback quality click the settings button (looks like a gear) after you've started the video.
Objective
Manufacturer's Specifications
Price: 90 USD
Dimensions
User Interface
The interface of the SRT3 has many options, but is incredibly intuitive. To turn the light on/off, you use the tail switch at the rear (half-press for momentary on or full press for constant on), and to control the output you use the control ring.
With the light pointing away from you, turning the ring all the way to the left will start you in the Beacon mode, steady quick bright flash at low frequency. Turning right, you next get the SOS mode, then a Red/Blue Strobe, then Blue, then Red, then the Minimum White output, then a smooth Infinitely Variable transition up to the Maximum White output, then a high-frequency Strobe. Each of these positions has a detent in the control ring so it feels like a soft "click" into position, providing tactile feedback and prevent the ring from changing position in you pocket. The exception is the Infinitely Variable section, which has a detent on either end for the Min and Max output, but is smooth in between.
Action Shots
You can click on any of these shots to see them full size.
Light in Hand (without and with AA extender)
White Wall (Low, Medium, High, Blue, Red)
ISO 100, f/3.3, 1/20"
(Blue and Red at 2")
BeamSlice
MugShot
Indoor Shots (Low, Medium, High, Blue, Red)
ISO 100, f/3.3, 1"
(Blue and Red at 10")
Outdoor Shots (Low, Medium, High, Blue, Red)
ISO 100, f/3.3, 2.5"
Long-Range Shots (High)
ISO 100, f/3.3, 5"
Performance
Submersion: I submersed the SRT3 under a foot of water for an hour, using the switch and control ring during that time, and found no evidence of water damaging or entering the light.
Heat: The SRT3 doesn't display any significant heat buildup.
PWM:
Drop: I dropped the SRT3 on various surfaces (carpet, grass, packed dirt, hard wood) and it did not suffer any cosmetic or functional damage.
Reverse Polarity Protection: The SRT3 uses mechanical reverse polarity protection to prevent the negative terminal of a battery from making electrical connection with the head.
Over-Discharge Protection: The SRT3 does turn itself off before over-discharging a lion, but as always, I recommend recharging the battery before this is necessary. The output of the SRT3 drops slightly before it's about to turn off, so that's your cue.
Spectral Analysis
All light that we see as white is actually made up of several different colors put together. The relative intensities of the different colors in the mix are what determine the tint of the white we see. For example, cool white LED's have a lot of blue, and warm white LED's have more red or yellow. This measurement was done on a home made spectrometer. The plot below the picture is corrected for the spectral sensitivity of the human eye. Note: the peak in the 900nm region doesn't really exist, it's a piece of the second-order spectrum that's showing up here because of the high intensity of the light source.
Output and Runtime
ANSI FL-1 runtime ratings are the time it takes for a light to fall to 10% of it's original output (counting from 30 seconds after turning the light on).
The vertical axis of the graphs below represents a relative brightness measurement using a home made light box. The horizontal axis is time in hours:minutes:seconds. Runtimes are stated in hours:minutes:seconds. These graphs may be truncated to show detail.
Mode Comparison
Max
Medium
Throwing Distance
ANSI FL-1 standard for stating a light's throwing distance is the distance at which the peak beam intensity (usually at the center of the beam) is 0.25 lux. I calculate throwing distance and candela (lux at 1 meter) by measuring peak beam intensity at five different distances and using the formula lux*distance^2=constant.
Peak Beam Intensity: 4532cd
Throw Distance: 135
(As a side note, Nitecore's claims are only 32cd off from what I measured, which is an impressive 0.7% error :thumbsup: )
Subjective Review
Quick break down:
+ Multi color option
+ Infinitely variable
+ AA extender included
+ High max brightness
+ Low min brightness
+ Very good regulation
+ Magnetic control ring
+ Indentations for modes
+ Perfect size for larger hands
+ Firm, screw-on clip
- A bit larger than some might EDC
I'll start by saying this light has replaced the SWM V11 as my new general purpose EDC, a position that was previously held by the SWM V10. This is a hard spot to get into, but the SRT3 has been nothing short of excellent.
My favorite aspect of this light has been the implementation of the magnetic control ring. So far, I've found the magnetic control ring to be the most practical and useful sort of user interface on a multi-mode flashlight for most uses. There are certainly a few uses where a standard switch is preferable, but for general use the magnetic control ring is incredibly intuitive and simple. For my mind at least, it helps to associate the modes with some physical position, instead of just some electronic setting--I know "where the mode is", not just a pattern of switching I have to follow to make it happen. On the SRT3 in particular, the magnetic control ring has been used very effectively. Each mode has it's own position on the control ring, and detents give some satisfying feedback to let you know when it's in the spot for the next mode and help to keep it from sliding out of that position accidentally. The infinitely variable portion of the ring has a detent at the max and min position, but a smooth travel over the intermediate settings so you can get the level you want. The max brightness is about 200 lumens for a AA, and up to around 650 when you use lithium ion batteries, and I've found even 200 lumens is plenty for most short to mid-range tasks in the dark. The minimum brightness is very low--lower than my SWM V10's or V11's, but not quite as low as my EYE10 TIC (which literally fades away into imperceptibility). I find the min is plenty low for reading something without destroying night vision or navigating a dark house without disturbing sleepers.
So far, I haven't found too much use for the red and blue modes other than to entertain my children, but for me that is a significant thing. I know that many people say the red and blue have certain tasks they are especially useful for in low light conditions, but I haven't had the opportunity to use them it those ways, so I won't comment on it at this point.
Taking a look at the output graphs above, you can see that the SRT3 has very good regulation, which is not really the norm for infinitely variable lights. Something about the electronics required for infinitely variable output seem to make regulation of that output harder, but Nitecore has done a good job here of combatting that effect. Also, you can see the regulation holds pretty well for both NiMH and Li-Ion batteries, which is uncommon.
I also want to point out the clip on this light. Many lights this size have a clip, but few of them make me feel confident that the light is secure in my pocket. This clip is held down by two screws, so it's not just a clip-on-clip that will fall off easily. It's also made of a metal that gives a firm hold without being too difficult to manipulate. This seems like a little thing, but it can make a big difference.
It's also worth noting that the AA extender is included with the light, so you don't have to buy a separate accessory. This is a nice touch, and adds a great deal of functionality. With some extenders I've used there can be trouble with the electrical connection when the extender is in place, but I haven't experienced that here.
The one possible drawback here is the size. The SRT3 is significantly larger than other lights in the single AA or single 16340 classes. It's got an excuse, with the magnetic control ring plus electronics for control of multiple emitters, but this still may be an issue for some. I find it has no trouble settling comfortably into my pocket, and the size is actually just right for my larger-than-average hands, but I can see for some people that it might be a bit larger than ideal.
So, the SRT3 is an all-together excellent general purpose light. I would not hesitate to recommend it to anyone looking for a EDCable single cell light. The magnetic control ring ensures that the multiple modes are not confusing or annoying but only very useful, the construction is on-par with Nitecore high quality, and the large size for its class is not any real hindrance to its use.
Long Term Impressions
I'll fill this part in after carrying the light for a while. If nothing get's added here, either I find nothing else worth noting about the light, or I end up not using it often.
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