Summary of Specifications
The Black Diamond Ion weighs 0.97 oz (27 g) with its single 6V battery. It is a 2-LED headlamp in a housing hinged and attached to a single, 0.5-inch wide elastic webbing strap that is adjustable with a band toggle.
The Ion has only one brightness mode, toggled between on and off with a single pushbutton switch, which is designed to be pushed with your thumb while your thumb and index finger ‘pinch’ the lamp. The switch is easily operable with bare hands or thin gloves, but nearly impossible with shelled mitts (with a thickness of 300 weight fleece). Changing the battery requires that the lamp be snapped from its housing, after which the casing can be snapped open to expose the battery compartment. The task requires some fine motor dexterity and finger strength, and is very difficult with cold hands. The pivoting head requires two hands to adjust the headlamp angle because of the instability of the headlamp housing against the head.
With fresh batteries at room temperature, the Black Diamond Ion has an initial center-of-beam brightness of 118 lux at a distance of 2 feet, falling off to 8 lux at 1 foot off the beam’s center.
In our cold conditions test (center-of-beam brightness 38 °F), the Ion’s lighting power was 42 lux at 0 hours (fresh batteries), 3 lux at 8 hours, and 1 lux at 24 hours.
The Ion is suitable as a short range headlamp for performing camp chores, but does not appear to have enough power for directional lighting in cold conditions. Even after 8 hours of continuous use with cold batteries, the Ion is generally unsuitable for short range task lighting.
The Ion’s cold weather performance is its primary weakness. It is a difficult light to use with mittens or cold hands, and cold weather lighting performance is poor, with its light output at 8 hours in our cold weather test inadequate for anything but dimly lit task lighting within 1-2 feet of the lamp. Light output after 24 hours was virtually nonexistent.
Note: To improve cold weather performance there is a 6v 160 mAh lithium photo cell option for the Ion (not tested in this review). Replace the manufacturer provided battery with a Radio Shack battery part number 23-266. Battery designations for other manufacturers are 2CR-1/3N, L544BP, PX28L, K28L.
The Ion is one of the lightest LED headlamps available. Its tiny form factor, light weight, and ability to use a lithium battery make it an attractive option for the ultralight backpacker.