Black Diamond designs some of our favorite headlamps. While we think the Spot is still the best value in headlamps, the newly introduced Iota puts a rechargeable battery and 150 lumens into a tiny package that disappears on your forehead. For some campers, the Iota may be the best headlamp option out there. Here’s our full review after weeks of use.

Features and Design

The Black Diamond Iota weighs in at a measly 52g (1.9oz) on our scale. That’s 4g under listed weight. (Always a bonus!) Physically, the Iota is aptly named. It’s tiny.

At its most powerful, the Iota shoots out a 150 lumen beam. You can dim that down significantly, but BD doesn’t list the low end lumens and we don’t have a meter, so we can’t tell you exactly how low it goes. Compare a high beam to a low beam (we tried to adjust the photos using the body of the headlamp as a control.  Didn’t quite work, but you get the idea.):

Black Diamond offers one-button control with the addition of their Powertap feature that lets you instantly jump from your current setting to full brightness and back. Brightness adjustments come via the usual BD mechanism – holding down the button when the headlamp is on.

black diamond Iota review

The Iota comes programmed to turn on at about 60% brightness. One of the cool features is that you can reprogram the initial brightness – BD calls it Brightness Memory. Set the brightness to your preferred level. Without turning the Iota off, plug it in to a power source. Once the small LED flashes green, unplug it and, within 25 seconds of unplugging it, hold down the main button. The small LED will flash blue, then yellow. When it has flashed yellow, the Iota is programmed to your specs. We have ours set to come on a the lowest setting.

Strobe mode is accessible with a triple-click. Holding down the button for four seconds locks the headlamp. Yes, it’s simple. It’s not meant to be a feature-rich torch.

Normally, headlamps have a ratcheting mechanism to adjust vertical angle. The Iota eschews such finery and relies solely on friction to stay in place. Without a positive engagement, it could be more prone to slipping. We haven’t experienced any issues with it yet. Over time, we expect that it may loosen up as the plastic parts wear against one another. It appears that the pivot is adjustable, so you can tighten it if it gets too loose.

black diamond Iota review

How we tested it

The Iota has been on dog walks (and recovery missions – that escaping rascal) and dawn patrols. It’s been on trail runs and hikes. We’ve used it for evening outdoor tasks.

Should you buy one?

Short answer, yes.

Long answer: yeeeeeeeeeeeeeeeeeeeeeees.

The Iota slips into a perfect little niche for headlamps. Rather than compete for the top lumen prize or pound it out with competitors (and BD’s other lights) for highest number of modes and features, the Iota presents a simple value proposition – it’s a relatively cheap, lightweight headlamp that puts out enough light for most tasks while eliminating the need to purchase batteries.  It’s also toddler-proof.

black diamond Iota review

Though it shouldn’t, the rechargeable nature of the Iota may cause some potential buyers to balk. If you’re not already entrenched in the rechargeable ecosystem and don’t carry solar or a backup battery pack, you can still use the Iota. The battery will last long enough for average use on a multi-day backpacking trip. If you’re not heading out for multiple days, it’s easy to plug the Iota in once in a while to top it up. That said, we’ve only had to charge it once so far.

If you want to have only one headlamp and see red every time you look at battery prices, the Iota is your little dude. Also, why do you want only one headlamp?