Field Report:
Black Diamond Cosmo Headlamp

Product Information Manufacturer: Black Diamond Manufacturer Website: http://www.blackdiamondequipment.com/ Product Tested: Cosmo Headlamp Year of Manufacture: 2006 Included: Headlamp, headband, 3 AAA batteries Number of LEDs: 4 Batteries Used: 3 AAA Number of Settings: 4 (high, medium, and low beam, plus strobe) Burn Time: 75, 120, and 150 hours for listed settings Illumination Distance: 59, 39, and 26 ft (18, 12, 8 m) for listed settings Weight: Manufacturer specified weight is 1.6 oz (44 g) without batteries, 2.8 oz (80 g) with batteries; measured weight is 1.65 oz (47 g) without batteries, 2.91 oz (82 g) with batteries (scale accurate to 0.01 oz/0.1 g) Warranty: 3 years MSRP: $29.95 US

The Black Diamond Cosmo Headlamp (Photo from Black Diamond website)

Summary
The Black Diamond Cosmo is a high quality general-purpose headlamp. It is exceptionally bright and useful for close-up work like camp chores, but it doesn’t quite put out enough light for trail hiking at night. It is very comfortable to wear and adjusts easily.

Product Description
From the Black Diamond website: “Tiny but packed with features, the Cosmo’s compact and lightweight design with four SuperBright LEDs provides bright, close-range lighting—stuff it in your pack, glove box or first aid kit for go-anywhere use.”

Features:
*  Low profile & super compact with tiltable head
*  3 brightness settings & strobe illumination
*  SuperBright LEDs provide good proximity lighting

Long-Term Report
Test Period—Mid-May 2006 to late September 2006.

Test Locations—Southern Colorado Mountains and Central Wyoming Mountains.

Testing Conditions—The testing environments consisted of forests and high elevation alpine country. Extreme conditions included: snow showers and one snowstorm, strong winds, thunderstorms, heavy rain, low temperatures, and high elevations. Terrains were forest trails, off-trail bushwhacking, scrambling, and walking in rain and snow. Elevations ranged from 6,000 to 13,500 ft (1829 to 4115 m) and temperatures range from 28 to 85 F (-2 to 29 C).

How The Headlamp Was Used —The Black Diamond Cosmo Headlamp was tested doing the following activities: 1) camp activities while backpacking, 2) backpacking at night, 3) reading in my tent, 4) cooking after dark, 5) night hiking, and 6) working at home on projects in poorly-lit situations.

Amount of Use—The Black Diamond Cosmo Headlamp was used on 15 trips totaling 37 days:

Data—On each trip I recorded the following data: 1) temperatures, 2) estimated wind speed, 3) estimated humidity, 4) altitude, 5) precipitation (including what form), 6) trail (or no trail) conditions, 7) how the Black Diamond Cosmo Headlamp was used, and 8) how well it performed in its various modes.

Factors Evaluated
Following are the specific factors on which I evaluated the Black Diamond Cosmo Headlamp.

Materials, Quality, And Construction—The headlamp case is made of molded plastic that appears to be a high-impact type that does not easily break. The headband is made of a soft, absorbent, stretchy fabric. Overall, the headlamp appears to be constructed of high quality durable materials.

Fit—Right out of its packaging, the headband fit my head perfectly. There is plenty of adjustment in the headband to fit over heavy headwear. I found it easy to adjust the headband from one situation to another. It fits and works well over a billed hat, which helps to direct the beam away from my eyes.

Comfort—The headlamp is comfortable to wear on my head for longer periods. I used it comfortably with a stretch hat, ball cap, and no hat.

Usability—The headlamp has four settings - high, medium, and low beam, plus strobe. A full depression of a large button on the top of the headlamp clicks to give the high beam. The medium, low, and probe (flashing light) settings are accessed by a half depression of the same button (no click). I had no problem finding the button and operating it by feel, even with gloves on.

I mainly used the Cosmo on its high setting, and occasionally switched to the medium setting while reading inside a tent or getting up at night for bladder relief. I never used the low setting or strobe.

Performance—The Cosmo really “shines” for close-up activities like cooking in camp, reading/writing/organizing in a tent, or working on a project in a location with poor lighting. It really lit up the area right in front of me, making it feel like daylight. It especially worked well in a tent, where the tent walls reflected the light to illuminate the entire tent.

When I used it for hiking on a rough trail at night, it barely put out enough light to adequately see the trail ahead of me. On one night hike with another couple, our friends used a headlamp designed for caving, and it lit up the trail much better than the Cosmo. A more powerful headlamp would definitely be better for night hiking.

On my last trip I got caught in an early September snowstorm, and spent 16 hours in my tent waiting out the storm. The Cosmo worked flawlessly inside the tent when I had to repeatedly slap the tent to make the snow slide off, and outside the tent when I had to dig snow away from the tent at night. The high humidity and moisture had no effect on the Cosmo’s performance.

The Cosmo also worked flawlessly in temperatures down to 28 F (-2 C), but I did not have an opportunity to test it at really cold temperatures. Presumably, the effect of cold temperature would mostly be on the batteries, not the headlamp.

Durability—I used the Cosmo headlamp, mostly on the high beam, over the course of four months and 14 trips, for a total of about 20 hours of burn time. That’s no where close to the estimated 75 hours that it is claimed to burn on one set of batteries. Needless to say, one set of batteries will last a long time.

Acknowledgement
I would like to thank Black Diamond and the BackpackGearTest Group for selecting me to participate in this test.

Will Rietveld