Photographer Chris Grey is an expert on lighting. He's written seven books on the subject, teaches classes and workshops, and is a strong advocate for precise control in the studio. To see more of his work, or to find his books and DVDs, visit his Web site.
Successful portrait lighting is all about the play of light upon the face, and the drama it creates for the viewer. One of my dictionaries defines drama as a “real-life event or situation that is particularly exciting or emotionally involving"—traits, I think, that any portrait should have. This definition would indicate that drama may be arrived at by many means and with many variations. In photography, the means is the light, and you create the variations. One of the variations in lighting that you can apply is the amount of diffusion between your subject and your light. Doubling the diffusion layer can help you shape the emotions provoked by a portrait through stronger or more subtle effects.
Bear in mind that this little exercise is not intended to lay down any new rules for portrait lighting. It's just a variation that may cause a creative synapse to fire within you. As always, I look for ways to separate my work (and yours) from that of the pack of competitors nipping at our heels.
We all know the value of soft light, whether from a softbox or an umbrella. Although an umbrella will produce a more contrasty light, this technique will enhance umbrella shots, too.
To begin, I placed my subject at what I feel is a versatile distance—about nine feet from the background, which was a basic white seamless paper. I used only one light, a strobe in a medium 3’x4’ softbox. There was no additional fill for this image, but only the light that was either wrapping around her or bouncing onto her. Since my key was aimed into a black wall, the bounce factor was minimal. This image is quite dramatic, in the usual sense, because the shadows are deep and the planes of the face are clearly defined.
When a white bookend is brought onto the set to bounce key light back to the subject, the shadows open up nicely and contour is maintained. This is a typical solution to the shadow “problem” evident in one-light portraiture, and it’s quite effective. Bear in mind that when you bring any bounce device into a previously metered situation you will have to re-meter to be accurate. Bringing the fill card to approximately three feet from the subject increased the exposure by 1/3 stop, from f/8 to f/9.
I wanted to see what would happen if my softbox light was diffused even further, so I hung a white nylon diffusion panel in front of the softbox. The additional baffle lowered the brightness of the light substantially, in my case almost a stop and a half, which required adjustment at the power pack to bring it back to the previous f/9. Of course, I could have made a smaller adjustment at the pack, to bring the exposure value to the nearest third of a stop, but that would have meant a change in the image’s depth of field.
The difference is quite remarkable. The additional diffusion, working with the bookend, acts as a perfectly controlled fill, opening the shadows even more than the bookend alone, and giving her skin a radiant, smooth look and adding detail to her hair.
You can accomplish much the same effect by using a white bed sheet in place of the diffusion panel. Be sure to re-meter and do a new custom white balance after the exposure has been corrected. I’m aware, of course, that some softboxes have secondary diffusion panels built into them (all of my Profoto boxes have that feature), but the extra diffusion will add to whatever degree of softness you get from your equipment.