If you’re of the seemingly rare breed these days of light meter enthusiasts, you may have heard the name ‘Lumu’ floating around. The original Lumu was crowdfunded via Kickstarter in 2013 and was a white-domed iPhone accessory that connected, unfortunately, to a phone via the headphone jack and turned it into a light meter. Unforeseen technological advances aside, in its release it possessed a critical shortcoming – many light meter users carry theirs to meter flash, and this original model couldn’t do that.

Two years later, however, the makers of Lumu were back with another Kickstarter, this time for the Lumu Power, which meters flash and then some. It is also a color meter, cine-meter, and spot meter with a host of features. The Kickstarter was fully funded with over 1,700 backers, and after some apparent production snags, units began shipping in April of 2017. They are now available at B&H, retailing for $299.


The Lumu Power is truly feature-rich, and it uses a lightning connector to take advantage of a greater capacity to transfer data compared to the prior headphone jack.

When you download and open the accompanying app, it turns your iPhone into a touch-screen handheld light meter with a sharp and vibrant screen that is very responsive to touch.

It can perform as a simple light meter, reporting brightness in ‘lux’; has an ambient mode for incident readings of available light; can be used as spot meter utilizing your phone’s camera; delivers video settings in the ‘Cine/Video’ mode; meters for flash, and measures color temperature and chromaticity.

In flash mode, it measures flash duration and can report in t.1 or t.5 and prepares a graphic representation of the flash. It can also give a percentage of ambient light versus flash that will appear in an exposure, which is helpful when mixing strobe and ambient light.

The individual modes can be easily customized, down to the brand of color filter you’re using and which ND filters you own in addition to the standard items like the choice of increment between stops display.

Most modes can create a graph averaging the data received over time.


The Lumu Power wraps the capabilities of many devices into one and offers some unique features on top of that. Retail price is on par with lower-end Sekonic meters, and simply, it does more.

Measured against a Sekonic flash meter, the Lumu Power matched within a few tenths of a stop, which is close enough for the difference to go unnoticed.

Color meters alone can be more than a thousand dollars, and while not as expensive as that, cine meters do cost a premium over simpler flash meters. Lumu Power does the job of multiple, more expensive devices.


The most prominent disadvantage applies to those who won’t be able to use the Lumu Power. If you don’t have an iPhone, you’re out of luck. As with so many similar situations, you can thank the iPhone’s standardization and few models for that – Android users aren’t shunned for the sake of it, but the diversity of devices makes things tougher for adaptation.

The size of the Lumu Power is both a benefit and drawback. While it’s easy to carry around without adding weight or taking up space in your camera bag, it’s so small that it is slightly nerve-wracking to keep safe. Its leather case does have a slit in the back so you can slide it onto a strap, which should help.

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It’s a minor inconvenience, but the color meter sensor is located on the flat back of the dome, so when you want to switch modes, for best results you’ll need to unplug the unit and flip it.

Being intrinsically tied to your phone, you will be at the mercy of your phone’s battery life to use Lumu Power, which is considerably shorter than that of a traditional light meter. Come prepared, and you should be fine, but it’s something to think about.


If you own an iPhone, have been shopping for a light meter, and trust yourself not to lose something tiny, there’s not much of a reason not to purchase a Lumu Power. It is extremely portable and works as advertised.

What do you think of the Lumu Power? Are you impressed by the pint-sized powerhouse or are you light meter-indifferent?