Sunday, January 29, 2012

Snoots and Grids

I spend a lot of time "playing" with new techniques, and just as much time refining old ones. It look upon these as tools that may, when applied judiciously at the right time, provide a photograph with more visual information to help the viewer more nearly "experience" the moment I attempted to capture.

Light Shaping: Light shaping has become something of an obsession with me. Whenever some new light shaping tool comes out, I respond in the same way as a carp approaching a doughball. One sniff, and cah-ching! It's mine.

Light modifiers fall into two categories: broad source and narrow source. Broad sources includes softboxes, umbrellas, and diffusion panels. They all allow the light to spread over a broader area resulting in a softer delineation between light and shadow. At the other end, there are light restrictors such as snoots and grids. Basically, a snoot can be a simple tube attached to the head of the speedlight. When it comes to light containment, a snoot only "suggests" where the photons will land.

Grids: Grids give you the ability to contain you light within a relatively small area. Their honeycomb construction constricts the light into tight cylinders with minimal spill on the edges. One such grid is the Rogue Grid from Expo Imaging. As you can see from the illustration on the manufacturer's web site, it consist of two grid disks that can be used together or separately. If you watch the video, you can see that the beam angle can be controlled to add light to a relatively small region. Unlike the snoot, it "directs" where the photon should go. For a detailed evaluation of the Rogue Grid, click here.

In The Field: I used a Rogue Grid for this shot at the Cantor Art Center on the Stanford University campus in Palo Alto, California.  "The Thinker" had just returned from a two-year loan to the North Carolina Museum of Art, and I was sent to photograph the homecoming.

Making an available light shot was pretty easy, but for this image I used two speedlights: One camera mounted SB-800 was used as a Commander/Fill light, and a hand-held SB-900 with the Rogue Grid would be used as a hand-held accent light. I had both of the Rogue's inserts in place to produce the narrowest beam possible. To make the shot, my D300 was set to manual (1/50 @ F 5.6, ISO 800, Cloudy WB). The lens was an 11-16mm Tokina. I wanted to add a very small amount of fill from the on-camera flash and some additional specular highlights on the Thinker's face from the gridded speed light. Because of the relatively high ISO, the speedlight power settings were set manually to 1/64 (with dome) for the SB-800 and 1/8 power for the gridded SB-900.

Pointing my gridded "spotlight" was a trial-and-error affair. I was standing next to one of the grand pillars surrounding the rotunda, which I used to support my wrist while I made test shots to "walk" the light onto the statue's face. I found that my first shots were poorly directed, blasting light into places I didn't want it to go. This, coupled with the constantly moving ensemble of workers demanded a lot of attention if I was to make a good shot. The submitted photograph, shown below, was number 91 of the 92 shots made during the assignment, which included earlier shots made from different angles.

The grid actually did two things: It kept light on the Thinker's face, and off the face of the worker beside him. Granted, there was some spill on the latter, but not so much as to be distracting. The high/camera left position of the gridded speedlight threw the shadow behind the statue, invisible to the viewer.

The photo ran the next day on the front page. I was pleasantly surprised how nicely the gridded speedlight added detail to the Thinker's face, making the iconic statue easy to recognize.

The Cantor Art Museum is located on the Stanford campus. Admission is free. And if you're over fifty and remember the pink section of the San Francisco Chronicle, as I am and do, you'll forgive my saying,

"Joe Bob says check it out."

To learn more about Joe Bob Briggs, click here.