Since light meters built in to our cameras are so good, why would we even bother with an external tool? A few reasons come to mind, most of them after spending some time with the Lumu light meter for the iPhone.
This small accessory plugs in to the headphone jack of the iPhone or iPad. And when used with its free iOS app, the Lumu measures the ambient lighting to help you determine an excellent starting point for exposure.
Here's a quick look at why I like using the Lumu.
Excellent Starting Exposure
Why not test the Lumu's capability while photographing the actual device in a mini popup studio with natural light? Take a look at the comparison.
As expected, the camera's patterned metering system under-exposed the shot (lower photo). This can be easily corrected with exposure compensation, of course. The Luma, however, nailed the exposure. When using the Lumu, I shot in manual mode and set the f/stop and shutter speed to the readout on the iPhone.
Manual Exposure Made Fun
Dialing in my own settings is now a snap. I use the readout displayed on the iPhone. That's it. Start taking pictures. I can ignore all of the blinking lights in the camera and focus on the composition.
Your photo subjects will be impressed as you take a light meter reading with your iPhone before the shoot. You may want to dress in all black and wear a beret to enhance the effect.
Great for Video
Video shoots are easy to set up using the Luma. You need to be in manual exposure anyway for video, so this accessory makes that process even easier.
Not everyone will want to spend $129 for an external light meter. But those who appreciate this type of photo tool will most likely love it. I bought my Lumu as a Kickstarter project and am very pleased with the investment. If you want to learn more about Lumu, visit the Lumu home page.