Woods Walker
The Wood is cut, The Bacon is cooked, Now it’s tim
Nitecore NU20 Headlamp CRI review.
For full disclosure these samples were sent to me from Nitecore for review.
http://flashlight.nitecore.com/product/nu20
Information from Nitecore.
Also Nitecore has the following runtimes listed for the CRI version and constant current no PWM.
1 lumen 100 hours.
30 lumen 7:45 hours.
170 lumens 6 hours.
270 turbo 30 minutes based on calculations.
So how do these claims hold up to actual field testing? The headlamp was designed for running but also used it for camping. First lets take a look at the headlamp. These are in CRI. It is so small and UL.
The reflector offered a good mix of throw and flood for running the trails and streets in my area.
The Nichia 219B LED looks centered with no obvious defects in the reflector or blemishes behind the window. For those who like the Nichia 219B the tint does not disappoint or at least I wasn't disappointed in the way it showed the true colors of bacon but that's coming up.
The back when attached to the headband. Hope I did it right.
Speaking of headbands this one is wide and comfortable. It's also big enough to fit my block head with more than enough extra room for adjustment. This is one of my biggest concerns for a headlamp. A good headband can make or brake it in terms of field effectiveness. However comfort can be subjective. For me this is a home run. So comfortable I feel asleep wearing it during one outing.
The harness has a physical lockout feature which proved 100% effective in my testing. Lock out is an important feature for me as often toss lights into a pack when on the fly.
The beam angle adjustment is done via two hinges and two friction points if I am using the right words to describe them. It took me two hands to adjust the beam angle when on the move as there isn't much headlamp mass to counteract the force needed for the adjustment. It doesn't slip during running.
The headlamp's Micro USB port cover.
and port.
With the physical characteristics out of the way time see if the claims hold up in field use. The first thing is charging. As the battery can't be replaced wanted to do some of the testing in field conditions. Nitecore claims it will charge in two hours. Here is what I found when charging if the light is off. The stated charge time was confirmed.
The switch turns red when charging.
Yes it will charge from a powerbank. In these cases the Nitecore F1.
Charging and running.
Just charging.
The light will operate when plugged in. Seems to operate at a max of medium if out of power running off a powerbank however does it charge and run at the same time? The answer is yes but appears to do it if running on low. I think it might be charging on medium as well but if so it would be at such a slow rate as to be not practical. On low it seemed to charge just fine.
Running on low and simultaneously charging test. Might seem like a strange test for a running headlamp but if pressed into other service it's a good feature. On a side note the USB cord hangs down the user's face if employed as headlamp when running off a powerbank but makes for a good handheld light or hands free if you don't mind the cable. This is more of an exceptional extra use type thing IMHO.
When plugged into a power bank running on low the UI button illuminates red however it's actually charging at a reasonable rate unlike my testing showed for medium.
Once charged it turns green just like having it plugged into a standard USB power source with the headlamp off.
After done the green light will turn off then fade. Many powerbanks terminate the charge once the device's battery is full so the light will stay on.
Bottom line. You can use it on low and it will run and charge at the same time. On medium not really.
So is there PMW? I did the shake and cellphone camera test using two devises. Also am sensitive to PWM so often see it when others can't.
On low there is no sign of PWM.
On medium there is something but not sure if it is actually PWM. Looks very similar to something I seen on my SC5w and didn't think it was actually PWM. Also could not detect it with the shake test. So can't say for sure but the cameras are picking up something. Just not convinced in my experience it is actually PWM. Maybe those more familiar with this technical aspect could key in.
The runtimes.
The price for the CRI is reduced efficiency so this headlamp has lower overall output but for the same time duration. I didn't bother to test if the 1 lumen would last for 100 hours. Sorry my short attention span just won't allow for that but did test the medium 30 lumen/7:45h and 170/6h. The 270 for 30 minutes is based on their calculations so didn't verify that.
Medium mode.
Still looked about regulated however began to drop soon after this photo. I ended the test with the light still functional but clearly in need of charging so there was some life left in it.
High mode. I ended the test with the light still functional but clearly in need of charging.
I didn't take a photo of the beam output as it looked a bit below the medium. So what happened? Per my hack math 600 mAh at 3.7 nominal volts is 2.22 watt hours. I don't know the draw of the headlamp but do not believe a Nichia 219B or Cree XP-G3 S3 can run their respected listed high output modes regulated for the entire time. So it steps down but does actually produce light at the 6 hour mark. It's probably within the rules for industry standards but just be aware it will not run the high regulated for the full 6 hours per my observations. Overall I am happy with the runtimes given the very small size of the headlamp and it's intended purpose.
Solar charging:
Did some solar testing of the Nitecore NU20. Seemed solar compatible using a 14 watt panel. I was unable to induce a charging error though your mileage might vary. This is one pro to USB powered devices. Charging from powerbanks and solar.
Solar Controller is missing an (o). I never noticed that before.
I didn't time it but charged good.
Water resistance testing.
The NU20 is IPX7 and 1.5m drop rated so decided to test both in actual field use conditions. First I would run 8 miles in the cold rain then drop the headlamp lamp multiple times in the roadside puddles. Jogged on both black top and dirt roads. Due to conditions only took the cellphone as it has a protective case.
One of 3 or so puddles tested for both drop and water intrusion.
Then left it out over night on the porch in the cold rain.
So what does running 8 miles in ice rain and slush feel like? It profoundly sucked. I liked nothing about it beyond the fact the NU20 survived the drops and water. I wasn't surprised the drops didn't harm it given the very low mass but was surprised no water got in. Sure it is IXP7 rated but still I am happy.
Up next was 5 miles through the hills trail running with mircospikes. Temps in the teens. Way better than 8 miles through the ice rain just above freezing but the terrain was harder. As this is a running headlamp most of the field testing was done on the fly but also took it camping Still it is a running headlamp so kinda had to run.
The low 1 lumen mode.
Plenty to walk around in and root through the pack back but wouldn't run on slippery ground with 1 lumen.
Medium.
High.
High projected a bit further.
Turbo.
Nichia 219B field application. Is it worth the reduced output?
Medium. Trail marker colors look true.
Medium. PSK high visibility paracord looked good.
The following is compelling proof of CRI's value. Look at how the bacon appears natural in the medium mode.
Fearing this might be just the camera I used another camera and verified what my eyes and the other camera were saying.
But how does cooked bacon appear under the illumination of a Nichia 219B?
Looks good with second camera as well.
Pros and cons.
Pros.
1. Two LED options.
2. Fast charge times.
3. Long regulated medium mode.
4. Very small and UL.
5. Comfortable.
6. Built in battery.
7. Nice beam for running and even camp work.
8. Very bright and nice low.
9. Will run when plugged into a powerbank. Will charge and run on low mode.
10 Headlamp angle doesn't slip when running. It stays put.
Cons.
1. Built in power source might be problematic as can't immediately change the battery.
2. The UL design means it is made out of plastic. Is what it is.
3. Is there PWM on that medium mode? Not sure. Don't think it is true PWM but something is going on.
4. The red flashing lights do work to indicate power to some degree but given their limitations can't be exact.
5. USB port position makes it difficult to wear and run off a powerbank at the same time.
6. Often takes two hands to adjust headlamp.
7. Yes it is a running headlamp but would love if they made a UL camping version with a 10 lumen mode. This isn't really a con rather a wish.
Conclusion.
I like it.
Here is a video.
For full disclosure these samples were sent to me from Nitecore for review.
http://flashlight.nitecore.com/product/nu20
Information from Nitecore.
Features ·Highly portable headlamp:
·Multiple color temperature options available
·NU20: Fitted with a CREE XP-G2 S3 LED
·NU20 CRI: Fitted with a Nichia 219B LED, CRI≥90
·Built-in Li-ion battery provides runtime up to 100 hours
·Onboard USB charging circuit
·Single switch user interface design offers easy one-handed operation
·Built-in power indicator (Patent No. ZL201220057767.4)
·4 brightness level and 2 special modes available
·Unique switch guard to prevent accidental activation
·Textured reflector
·52°adjustable illumination angle
·Made from durable PC materials
·Lightweight and compact dimensions
·Impact resistant to 1.5 meter
Dimensions:
Size: 2.18"×1.29"×0.82"(with bracket)
Weight:
1.66oz(with battery and bracket)
Operating Instructions:
ON/OFF
Draw out the NU20/NU20 CRI to expose the switch from the switch guard as
illustrated in the diagram below, press the switch to turn the light on, pressing the
switch again after 3 second to turn the light off
Note: Pressing the switch again within 3
second from when the light is turned on will
switch output to the next available brightness.
Brightness Adjustment:
Press the switch repeatedly within 3 second from the initial activation will switch
output from ultralow-mid-high-off. Pressing the switch again after 3 second from
initial activation turns the light off.
Access to Turbo
With the light turned on, hold down the switch for more than 1 second to enter
turbo mode (360 lumens for NU20 and 270 lumens for NU20 CRI).
Note: The turbo mode will run for 30 second before stepping down to the next
available output to prevent overheating.
Special Modes: (SOS/Location Beacon)
With the light turned off, hold down the switch for over 3 second to enter SOS,
pressing the switch again within a 3 second interval to switch to location beacon.
To exit special mode, press the switch in location beacon mode, alternatively,
cease any operation for 3 second then press the switch again.
Power Tips:
With the light turned off, hold down the switch for 1 second, the power indicator
will blink to indicate remaining battery power upon the release of the switch: 3
blinks represent battery power above 50%, 2 blinks represent battery power below
50%, 1 blink represents battery power below 10%.
Note: Recharge the product when output appears to be dim and/or unresponsive.
Recharging:
1.This product is USB rechargeable. Raise the micro-USB port cover to expose
the charging port, connect the port to a power supply with a USB cord to initiate
the charging process. Fully charges the battery take approximately 2 hours
2. Charging Tip: A red light under the switch will be lit to
indicate charging in progress, and it will turn green
upon charging completion
Also Nitecore has the following runtimes listed for the CRI version and constant current no PWM.
1 lumen 100 hours.
30 lumen 7:45 hours.
170 lumens 6 hours.
270 turbo 30 minutes based on calculations.
So how do these claims hold up to actual field testing? The headlamp was designed for running but also used it for camping. First lets take a look at the headlamp. These are in CRI. It is so small and UL.
The reflector offered a good mix of throw and flood for running the trails and streets in my area.
The Nichia 219B LED looks centered with no obvious defects in the reflector or blemishes behind the window. For those who like the Nichia 219B the tint does not disappoint or at least I wasn't disappointed in the way it showed the true colors of bacon but that's coming up.
The back when attached to the headband. Hope I did it right.
Speaking of headbands this one is wide and comfortable. It's also big enough to fit my block head with more than enough extra room for adjustment. This is one of my biggest concerns for a headlamp. A good headband can make or brake it in terms of field effectiveness. However comfort can be subjective. For me this is a home run. So comfortable I feel asleep wearing it during one outing.
The harness has a physical lockout feature which proved 100% effective in my testing. Lock out is an important feature for me as often toss lights into a pack when on the fly.
The beam angle adjustment is done via two hinges and two friction points if I am using the right words to describe them. It took me two hands to adjust the beam angle when on the move as there isn't much headlamp mass to counteract the force needed for the adjustment. It doesn't slip during running.
The headlamp's Micro USB port cover.
and port.
With the physical characteristics out of the way time see if the claims hold up in field use. The first thing is charging. As the battery can't be replaced wanted to do some of the testing in field conditions. Nitecore claims it will charge in two hours. Here is what I found when charging if the light is off. The stated charge time was confirmed.
The switch turns red when charging.
Yes it will charge from a powerbank. In these cases the Nitecore F1.
Charging and running.
Just charging.
The light will operate when plugged in. Seems to operate at a max of medium if out of power running off a powerbank however does it charge and run at the same time? The answer is yes but appears to do it if running on low. I think it might be charging on medium as well but if so it would be at such a slow rate as to be not practical. On low it seemed to charge just fine.
Running on low and simultaneously charging test. Might seem like a strange test for a running headlamp but if pressed into other service it's a good feature. On a side note the USB cord hangs down the user's face if employed as headlamp when running off a powerbank but makes for a good handheld light or hands free if you don't mind the cable. This is more of an exceptional extra use type thing IMHO.
When plugged into a power bank running on low the UI button illuminates red however it's actually charging at a reasonable rate unlike my testing showed for medium.
Once charged it turns green just like having it plugged into a standard USB power source with the headlamp off.
After done the green light will turn off then fade. Many powerbanks terminate the charge once the device's battery is full so the light will stay on.
Bottom line. You can use it on low and it will run and charge at the same time. On medium not really.
So is there PMW? I did the shake and cellphone camera test using two devises. Also am sensitive to PWM so often see it when others can't.
On low there is no sign of PWM.
On medium there is something but not sure if it is actually PWM. Looks very similar to something I seen on my SC5w and didn't think it was actually PWM. Also could not detect it with the shake test. So can't say for sure but the cameras are picking up something. Just not convinced in my experience it is actually PWM. Maybe those more familiar with this technical aspect could key in.
The runtimes.
The price for the CRI is reduced efficiency so this headlamp has lower overall output but for the same time duration. I didn't bother to test if the 1 lumen would last for 100 hours. Sorry my short attention span just won't allow for that but did test the medium 30 lumen/7:45h and 170/6h. The 270 for 30 minutes is based on their calculations so didn't verify that.
Medium mode.
Still looked about regulated however began to drop soon after this photo. I ended the test with the light still functional but clearly in need of charging so there was some life left in it.
High mode. I ended the test with the light still functional but clearly in need of charging.
I didn't take a photo of the beam output as it looked a bit below the medium. So what happened? Per my hack math 600 mAh at 3.7 nominal volts is 2.22 watt hours. I don't know the draw of the headlamp but do not believe a Nichia 219B or Cree XP-G3 S3 can run their respected listed high output modes regulated for the entire time. So it steps down but does actually produce light at the 6 hour mark. It's probably within the rules for industry standards but just be aware it will not run the high regulated for the full 6 hours per my observations. Overall I am happy with the runtimes given the very small size of the headlamp and it's intended purpose.
Solar charging:
Did some solar testing of the Nitecore NU20. Seemed solar compatible using a 14 watt panel. I was unable to induce a charging error though your mileage might vary. This is one pro to USB powered devices. Charging from powerbanks and solar.
Solar Controller is missing an (o). I never noticed that before.
I didn't time it but charged good.
Water resistance testing.
The NU20 is IPX7 and 1.5m drop rated so decided to test both in actual field use conditions. First I would run 8 miles in the cold rain then drop the headlamp lamp multiple times in the roadside puddles. Jogged on both black top and dirt roads. Due to conditions only took the cellphone as it has a protective case.
One of 3 or so puddles tested for both drop and water intrusion.
Then left it out over night on the porch in the cold rain.
So what does running 8 miles in ice rain and slush feel like? It profoundly sucked. I liked nothing about it beyond the fact the NU20 survived the drops and water. I wasn't surprised the drops didn't harm it given the very low mass but was surprised no water got in. Sure it is IXP7 rated but still I am happy.
Up next was 5 miles through the hills trail running with mircospikes. Temps in the teens. Way better than 8 miles through the ice rain just above freezing but the terrain was harder. As this is a running headlamp most of the field testing was done on the fly but also took it camping Still it is a running headlamp so kinda had to run.
The low 1 lumen mode.
Plenty to walk around in and root through the pack back but wouldn't run on slippery ground with 1 lumen.
Medium.
High.
High projected a bit further.
Turbo.
Nichia 219B field application. Is it worth the reduced output?
Medium. Trail marker colors look true.
Medium. PSK high visibility paracord looked good.
The following is compelling proof of CRI's value. Look at how the bacon appears natural in the medium mode.
Fearing this might be just the camera I used another camera and verified what my eyes and the other camera were saying.
But how does cooked bacon appear under the illumination of a Nichia 219B?
Looks good with second camera as well.
Pros and cons.
Pros.
1. Two LED options.
2. Fast charge times.
3. Long regulated medium mode.
4. Very small and UL.
5. Comfortable.
6. Built in battery.
7. Nice beam for running and even camp work.
8. Very bright and nice low.
9. Will run when plugged into a powerbank. Will charge and run on low mode.
10 Headlamp angle doesn't slip when running. It stays put.
Cons.
1. Built in power source might be problematic as can't immediately change the battery.
2. The UL design means it is made out of plastic. Is what it is.
3. Is there PWM on that medium mode? Not sure. Don't think it is true PWM but something is going on.
4. The red flashing lights do work to indicate power to some degree but given their limitations can't be exact.
5. USB port position makes it difficult to wear and run off a powerbank at the same time.
6. Often takes two hands to adjust headlamp.
7. Yes it is a running headlamp but would love if they made a UL camping version with a 10 lumen mode. This isn't really a con rather a wish.
Conclusion.
I like it.
Here is a video.
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