Today’s Post by Joe Farace
I think it’s obvious that LED studio lighting is a trend that isn’t going away any time soon. But if you’re new to working in the studio with LED lighting systems, as I did with Flashpoint’s affordable ($49) CLAR CL-500R Pro DiskLight Bi-Color SMD Flood LED Circular Light, it brings you face-to-face with terms like lux, lumens and foot-candles.
Don’t let these buzzwords freak out; there was a time when megapixels were alien too. Lux is a unit of illumination that’s equal to one lumen per square meter or the equivalent of 0.0929 foot-candles. Sekonic offers a chart that compares Exposure Value to foot-candles and lux. Charts, such as Jim Beecher’s, show the relationships of shutter speed to aperture at a given EV for a specific ISO setting so with a little practice you can convert these numbers into shutter speed and lens apertures if only on a order of magnitude basis, such as when you discovered that the Nikon D850 had 45.7 megapixels, you knew “that’s a lot of megapixels.” Or you can just ignore all this and use the light meter built-into your camera, which is what I do, using the meter’s incident setting.
But it’s not just he way that light from LED sources is measured it’s also the quality of that light because not all individual LEDs are equal and can vary batch-to-batch. The bottom line is that although some cheap LED lights reflect their price point other inexpensive lights are surprisingly good, just as some expensive LEDs lights are not all that great. And there doesn’t seem to be a direct correlation between price and quality of LEDs. Some lights exhibit a characteristics called Pulse Width Modulation; you can see an example of this, with this very same model on this post.
To measure this quality of LED studio lighting, I purchased a pocket-sized Diffraction Grating Spectroscope that lets me inspect a light source’s spectrum and actually see peaks and missing bands. These devices are also used by rock and mineral collectors and you can find them on eBay or Amazon for about $45. Although your eyes automatically adjust for missing color bands or spikes, your camera cannot and this difference results in time spent or wasted, depending on your interpretation, in the digital darkroom trying to get the color “right.”
How I made this shot: I photographed Sarah in my home studio using an Olympus E-M10 Mark I and Olympus 14-42mm f/3.5-5.6 II R lens (at 42mm) with an exposure of 1/50 sec at f/5.7. One of the CL-500R LED lights was placed at camera left with a 33-inch white Flashpoint umbrella mounted. A second LED light was placed at camera left and was covered with a diffusion sock that I had laying around the camera room.
A Lastolite Distressed Paper collapsible background was used as backdrop and was leaned up against a background already hanging from my falling-apart JTL background stand.
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If you’re interested in learning how I shoot portraits and how I use cameras, lenses and lighting in my in-home studio and on location, please pick up a copy of Studio Lighting Anywhere which is available new from Amazon.com for $20.26 or starting at the bargain price of $5.53 used, as I write this. Kindle version is $11.99 for those preferring a digital format.