by the Product Review Staff | 2003-12-10 03:00:00-07
The Black Diamond Zenix weights 4.54 oz (129 g) with 3xAAA batteries. It is a 3-LED headlamp with two modes that alternate between a central, "hyperbright" LED and two peripheral standard LED's. Batteries are located in a rear housing and the headband is a conventional bucket-style with 3/4-inch elastic webbing.
The Zenix has two modes: a "high" mode that uses the central lens-focused hyperbright LED, and a "low" mode using the two convenetional peripheral LEDs. The modes are toggled by the pushbutton switch that is designed to be activated with your thumb while your thumb and index finger pinch the lamp housing. The swith can be operated with bare hands or thin gloves, but not with heavily insulated gloves or mittens one might use in the winter.
The Zenix has the best battery compartment of the bunch, with access provided by a knurled thumbscrew (that doesn't fall out after opening the lamp, and thus, cannot be lost in the field) and batteries that sit securely in their sockets. We were able to successfully change batteries in the field while wearing heavily insulated (300-weight fleece) shell mitts with full leather palms, a task we could not perform with any other headlamp in the review.
The Zenix has a tiltable lamp housing that pivots smoothly and is easily adjustable with one hand.
With fresh batteries at room temperature, the Black Diamond Zenix has an initial center-of-beam brightness of 438 lux at a distance of 2 ft (0.6 m), falling off to 7 lux at 1 ft (0.3 m) off the beam’s center (high setting). The center-of-beam intensity on the Zenix' low setting was 125 lux.
In our cold conditions test (center-of-beam brightness 38 °F), the Zenix’s lighting power at its high setting (hyperbright LED) was 397 lux at 0 hours (fresh batteries), 223 lux at 8 hours, and 44 lux at 24 hours. At its low setting (standard LEDs), corresponding intensity levels were 115 lux (0 hours), 14 lux (8 hours), and 6 lux (24 hours).
The Zenix is well suited for navigation lighting, throwing a beam that is both long and bright enough for off-trail nightime navigation or moutaineering use. In its low intensity mode, the lamp provides plenty of illumination for short range task lighting. In short, the Zenix is the first all-LED headlamp we've reviewed that can effectively perform both task and navigation lighting exceptionally well.
The Zenix' 2-side-LED proximity lighting mode suffers from poor power drain and intensity fall-off. Lack of voltage regulation and the inability to use lithium batteries certainly contribute to this performance. It is interesting to note that the Princeton Tec Scout (powered by lithium coin cells) maintains approximately the same intensity levels at cold temperatures for 8-24 hours of operation.
What is most remarkable, is that the Zenix provides higher intensity light output over longer time when operated in its hyperbright mode in cold conditions! Thus, we're wondering why the two peripheral LEDs and the low brightness setting are even available, since the latter drains the batteries faster!
As with other Black Diamond headlamps, the button switch of the Zenix is small, tucked under the angled bottom of the headlamp, and difficult to operate with gloved or mittened hands.
All is not lost! The Zenix uses a lens-focused hyperbright LED that puts out an intense and narrow beam that has light output that exceeds many halogen bulbs. Surprisingly (given the fact that it uses AAA batteries), the Zenix had excellent cold weather performance, exceeding the performance of headlamps with lower-wattage LEDs powered by Lithium AA cells. The only brighter lamp in our review was one that used a higher-powered 1-watt LED, and the Zenix was the brightest of all of the LED headlamps tested after being continuously operating for 24 hours in cold conditions.
Changing batteries is a cinch in the Zenix and its battery housing design is mitten-friendly.
At 4.5 oz with batteries, the Zenix is the lightest "high intensity" headlamp on the market and an oustanding choice for someone looking for a long-lasting navigational light.
"Black Diamond Zenix Headlamp Review," by the Product Review Staff. BackpackingLight.com (ISSN 1537-0364).
http://backpackinglight.com/cgi-bin/backpackinglight/00267.html, 2003-12-10 03:00:00-07.