More About Shooting With Portable Lighting

More About Shooting With Portable Lighting

by William Lulow

I had just finished a headshot session indoors with my normal studio lighting setup and we decided to go outside on the deck to do some shots with a soft, leafy background. The sun had come out for a bit and I had all my portable lighting equipment ready. My portable kit consists of two older Sunpak 120J flash units, both with their own lithium ion power sources, a Canon 430exII flash unit for my camera, if I need it, and my Pocket Wizard radio system to control them all. I also use a special rig with an umbrella to soften the light even further. Here is a shot of me shooting the subject outside:

I use a little kind of homemade pouch, to hold the battery and the Pocket Wizard and they are all mounted on the light stand for easy portability. Now for these images, I needed to fill in the subject’s face a bit with a second light. Here is the placement of that light:

So, there are a couple of lighting principles operative here. One is that in order to create really soft light, the light source has to be large in comparison to the subject. I have said this many times, but if you think of the sun as really a “point light source,” you can see the effects of the shadows it casts here on earth. They are quite distinct and often obscure details that you would want to see. The other thing you may notice in this image is how far away my fill-in light source is from the subject and how close the umbrella light is. That’s because I wanted the umbrella light as large as possible, since it was the main source of illumination. You may also notice that the fill-in light is used “raw” with no diffusion. The mainlight (with the umbrella), because it is bounced, is much weaker than the fill, thus accounting for the greater distance of the secondary light.

One of the other lighting principles that you would have to know in this situation is that portable lighting produces only a fraction of the light that regular studio flash units do. So, my exposures outside here were something like f/5.6 @ 1/100th of a second using ISO 400. Not only did I have to compensate for the smaller amount of power, but I also had to think about the flash-to-subject distance as well. Also note here that one of the flash units is bounced into the umbrella while the other is used “raw” with no diffusion at all. That accounts for how far back it was placed. Here is one of the results:

When shooting with most portable flash units, you have to take into account that they are not as strong as studio units and therefore, exposures have to be adjusted accordingly. It turns out that these shots were made with the more exposure indicated above. In the studio, the exposure would have been f/11 @1/100th of a second with ISO 100. The sun was not so strong in this image so it only created a small accent light on the woman’s shoulders and hair.

Here’s the studio version. The exposures were f/11 @ 1/125th of a second using ISO 100: