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Fenix has been a leader in the high-end flashlight industry for the past several years, popular among flashaholics and "normal" people alike. They have flashlight models of all shapes and sizes, and now they've added another headlamp to their lineup. It's got two XP-E emitters, one set up as a flood light and the other as a spot light, hooked to a 4xAA battery pack in the back, so you're ready for all sorts of headlamping situations.


Thanks to Fenix for providing the HP25 for review.

I’ll be reviewing the HP25 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.

Quick Overview

Below is a video "quick review" you can watch in just a few minutes, if you're not up for reading the full review right now:



https://www.youtube.com/watch?vfBIESKDYdY

This video is available in 720p 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: 70 USD




this image provided by Fenix


Packaging



The HP25 comes in a cardboard/plastic package displaying all the light's stats, and includes 4xAA batteries.


Construction




The Fenix HP25 is a headlamp-format light, set up with the emitters in front and the 4xAA batteries in a separate pack in the back, connected by a spiraled cord for stretchiness. The majority of the body and battery case are made from plastic.



Both emitters feature a lens with an anti-reflective coating for maximum light transmission.



Both emitters are CREE XP-E's, so if they used the same optics they would have the same beam patterns. However, one is set up in a deeper reflector (on the left as you view it from the front) to focus the beam to a tight spot, and the other uses a combination of very shallow reflector and aspheric lens (on the right) to spread the beam to a very wide and even flood.



The Fenix logo is between and above the two emitters, and the light is controlled by two electronic switches along the top edge of the light. The one controlling the spot emitter has a symbol of parallel beam lines, the one controlling the flood emitter has a symbol of diverging beam lines.



On one side of the light, the cord comes out to go around your head back to the batter pack. On both sides, a hinge with ridges to gives the HP25 an adjustable angle.



The front part of the HP25 (that houses the emitters) is mounted by a hinge on a base where the headband attaches, so that you can adjust the angle of the beam. The above animation shows the various angle available.



This is the base of the HP25 where the headband attaches.



This is the battery pack, which sits on the back side of your head.



The battery pack unscrews and a clear plastic battery case slides out.



The four slots of the batteries are marked for polarity, with springs for the negative terminals. The threads for the screw holding the case together are metal, not plastic.



The HP25 comes with four Pairdeer AA batteries included.



Attaching the headband takes some time to figure out at first, but it works very well once attached. Because of the weight involved in using the four AA batteries, it requires both a strap around the side and one over the top to keep it from sagging.



The headband attaches to slots on the inside of both the light and the battery pack. Two small clips hold the cord to the headband so it doesn't hang loose.

Dimensions



Accessories



The HP25 comes with the light, battery pack, 4xAA Pairdeer alkaline batteries, headband side strap, headband top strap, warranty card, manual, and two cord clips.

User Interface



The HP25 has two emitters, independently controlled by two electronic buttons. Each emitter is controlled by the button directly above them, the Spot button labeled with parallel lines and the flood button with diverging lines. Each emitter has four available modes, though not the same modes.

To turn an emitter on, hold down the button for about a second. To change the brightness, pressing the button will advance you to the next mode in the sequence. For the Flood emitter, the sequence is Low -> Medium -> High -> Turbo. For the Spot emitter, the sequence is Low -> Medium -> High. The fourth mode of the Spot emitter is SOS, which is accessed by holding down the Spot button for about two seconds (whether the emitter is currently on or off). To turn an emitter off, hold down on it's button for about a second.

The emitters are controlled completely independently, so either can be on any mode or off at any time without being affect by the mode of the other.


Action Shots

You can click on any of these shots to see them full size.

Light in Hand


White Wall
ISO 100, f/3.3, 1/20"
Flood: Low, Medium, High, Turbo
Spot: Low, Medium, High
Flood Turbo + Spot High




BeamSlice
Flood, Spot, Flood+Spot


MugShot
Flood, Spot


Indoor Shots
ISO 100, f/3.3, 1"
Flood: Low, Medium, High, Turbo
Spot: Low, Medium, High
Flood Turbo + Spot High




Outdoor Shots
ISO 100, f/3.3, 2.5"
Flood: Low, Medium, High, Turbo
Spot: Low, Medium, High
Flood Turbo + Spot High




Long-Range Shots
ISO 100, f/3.3, 5"
Flood Turbo, Spot High, Flood Turbo + Spot High



Performance

Submersion: Fenix has rated the HP25 at IPX-6, which for water resistance is labeled "powerful water jets". This means it's not approved to survive being completely submersed, but it has passed a test of having high-powered jets of water squirted at it from all directions. I don't have any powerful water jets, so I squirted it from all angles with the most powerful squirt gun I could find. I could find no evidence of water entering or damaging the light, however the strap did of course get soaked and took time to dry out.

Heat: I notice no heat buildup on any mode of the HP25.

PWM: I did not detect pulse-width modulation on any mode of the HP25.

Drop: I dropped the HP25 from a height of one meter onto various surfaces. I found no cosmetic or functional damage to the light.

Reverse Polarity Protection: Fenix claims the HP25 has reverse polarity protection for all the battery slots, so if any combination of 1, 2, 3, or all 4 batteries are inserted backwards the light will not be damaged. I tried reversing the batteries in all 15 possible combinations, and the light did not turn on when any battery was reversed. Afterward, I corrected all the batteries and the light resumed normal operation, with no sign of damage.

Over-Discharge Protection: The HP25 does not accept lithium ion batteries, so over-discharge protection is not necessary.


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.

As you can see, the flood emitter in my review sample is noticeably cooler than the spot emitter, which is reflected in the beamshots as well.

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

All of these graphs are truncated to show detail, the HP25 runs on for quite some time on very low output for each mode.

Food + Spot



Flood



Spot



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.

Flood + Spot
Peak Beam Intensity: 5573 cd
Throw Distance: 149 m

Flood
Peak Beam Intensity: 120 cd
Throw Distance: 22 m

Spot
Peak Beam Intensity: 5415 cd
Throw Distance: 146 m

I measured the throw for Flood + Spot independently of the Flood and Spot measurements (I didn't just add the Flood and Spot together for a calculated Flood + Spot), but the measurements are very close to what I would get if I did just add them. This shows that the HP25 is perfectly capable of running both emitters at full power at the same time.

Subjective Review

Quick break down:

+ Separate flood and spot emitters!
+ Excellent regulation with NiMH
+ Very accurate output claims
+ Headband is comfortable
+ Adjustable light angle
+ Common battery type
+ Spot and flood beams controlled separately
+ Smooth mode transitions
+ Output relatively high for a headlamp

- Mode labeling is just weird
- Heavier than single-battery headlamps
- Emitter tints don't quite match

The HP25 has been a very impressive headlamp. Using four AA batteries and two XP-E emitters, it's in the "large" range for headlamps and is brighter than most, but doesn't rival contemporary hand-held lights in brightness. The only headlamps that have significantly higher output than the HP25 are those few that mimic handheld lights using an 18650 lithium ion battery.

Number one high point of the HP25 is it's dual-emitter system, focusing one for a tight spot and dispersing the other for an extremely even flood. The flood is so even, that in normal outdoor use it's almost impossible to identify a hot spot at all. It's also great that both emitters are controlled independently, so you hace have whatever combination of flood and spot that you need--this was a great decision on the part of the designers. Depending on my environment, I found myself using flood only, spot only, or a combination of the two. While using it indoors, the flood alone was great for lighting up a whole room extremely evenly, which makes it easy to see everything going on without being blinded to your surroundings. Late at night around the house the 4 lumen mode is good for not ruining your night vision or waking up family. The higher modes worked well for lighting up a larger room and working in it. I found myself usually only turning on the spot when outside. For general going for a walk, I usually used the flood on High and and the spot on Medium. For biking, I turned both emitter on max and had the entire area lit so I could see all my surroundings, plus I could see a long distance down the path.

One of the big concerns with a headlamp is comfort over the long term, so you can use it for full night without getting a headache. The wide, stretchy band provided with the HP25 was definitely comfortable on my head, and the addition of the band over the top meant I didn't have to have the headband very tight in order for the light to have enough support to stay in place. The adjustable angle feature meant I could mount the light wherever was most comfortable on my forehead, then adjust the angle accordingly. The addition of the battery pack on back meant the light was well balanced on my head, but over a long period of time I could definitely notice a difference from smaller single-cell headlamps, though not enough to cause any pain or fatigue.

From a technical standpoint, I was very impressed with the extremely accurate output claims for the HP25--I measured output level at or above those claimed on almost every mode. Where the max is claimed at 360 lumens for both emitters combined, I actually measure 395 on NiMH and 423 on alkalines. Also, the regulation on each mode is absolutely excellent. After a very small ramp down at the beginning as the battery voltage levels out, the regulation is near perfect for the duration of the main run. Then, the light quickly drops to a very low (lub-lumen) output and stays on at that level until the batteries give out. This is great, because you have reliable light without dimming for the expected run time, then an obvious alert that your batteries need changed, followed by plenty of time to find the fresh batteries while you still have a little bit of light. This is pretty much exactly what I like to see in an output graph. The ANSI values for run time that I measured where slightly lower than what Fenix reported, but this may be due to the fact that my NiMHs are 1900 mAh, where I believe 2000 or more is pretty standard now. One more technical thing to note, is that on the HP25 the mode transitions have a quick smooth ramp instead of an abrupt change. It takes much less than a second, but it's noticeable that one mode ramps up to the next. I don't know if this is standard for Fenix (this being my first Fenix to review), but it's not standard for most lights and it's a pleasing touch.

There are very few negatives I found for the HP25. I did already mention the size and weight, which some may consider a negative depending on your desired usage, but really it's a tradeoff that you have to make in order to get the high output and run time from a common battery type. My one real (though petty) gripe with the HP25 is that the mode labeling is just weird. I'll re-post the graph here to explain:


this image provided by Fenix

For some unfathomable reason, Fenix decided to offset the mode labeling so that while both emitters have a 180 lumen mode, one is called "Turbo" and the other is called "High". Thus, only the flood emitter has Turbo (though it doesn't behave like a Turbo mode, it's fully regulated like all the others). High mode for the flood emitter is 90 lumens and High for the spot is 180 lumens; same problem with Medium and Low. Why not ditch the Turbo label, and instead call the flood's 4 lumen mode "Very Low" or something, then everything's peachy. Does this actually affect the performance of the light in any way? Nope. But it made it a pain for me to keep straight doing the review, and it just seems like a pointlessly silly decision by whoever at Fenix made this chart. :shrug:

Other than that, the only other negative is that the emitter tints aren't quite matched. As you can see in the Spectral Analysis section, the flood emitter is measurably cooler than the spot emitter. This isn't a huge issue and will only bother the most picky of eyes in real use. This could be due to the different optics used, because a reflector handles light differently than a lens, so that even two emitters with the same tint bin and color temperature would end up appearing different when inserted into these two different optics.

Overall, the HP25 is an excellent headlamp. If you're looking for a high quality headlamp and are willing to have the extra size and weight for the benefits of higher output, longer run time, and independently controllable spot and flood emitters, then the HP25 would be a great choice.


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.