HDR: Part 36 - Finding Focus: Good ACs Have To Feel It

Was it to embarrass me or simply the only way to get the shot?

On a New York stage in the 1980s, early in my career working as an assistant camera person, the DOP had concocted a 360º dolly move around a pair of actors dancing cheek to cheek. With beads of sweat rolling down my face, I grappled to find and hold focus shooting wide-open with a 50mm lens. Such a scenario would pose a challenge to even an experienced AC, but for me, a newbie, it was enough to instill sheer panic. In retrospect, I was fortunate not to be working T1.3 with a Super Speed, but even with the standard lens at T3.1, I didn’t have a lot of leeway for error.

After two botched takes, it was clear I was struggling, so the DOP felt obligated to step in. Enlisting the help of a grip, he tied one end of a clothesline to the Chapman Mitchell plate, and the other end to the waist of one of the actors just below the frame line.

A camera operator may not always be able confirm critical focus in low contrast scenes with a narrow depth of field. The operator and DOP need the expertise of a well-versed AC to verify all is well.

A camera operator may not always be able confirm critical focus in low contrast scenes with a narrow depth of field. The operator and DOP need the expertise of a well-versed AC to verify all is well.

Constraining the actors’ movement in this way helped maintain a constant distance from the camera, and in the end, I was able to land the shot. The clothesline trick was ingenious – I’m the first to admit it, I still teach it in my classes - but the spectacle of it, broadcast in such a public way, humiliated me.

After wrap that day, the DOP pulled me aside to offer a few words of wisdom. He said my approach to following focus was too mechanical, too reactive. I needed to feel the shot and not rely so much on witness marks on the lens or the actors hitting pre-proscribed reference points.

At first, I didn’t quite get it but eventually the idea sank in. I was consistently late pulling focus because I was glued to the lens and FF, instead of watching and anticipating the action in front of me. 

With the help of digital rangefinders and wireless transmitters, focus pullers have access to a range of increasingly sophisticated tools. The need to feel a shot in order to execute proper focus is still there.

With the help of digital rangefinders and wireless transmitters, focus pullers have access to a range of increasingly sophisticated tools. The need to feel a shot in order to execute proper focus is still there.

Today’s ACs, who follow-focus from a monitor, face a similar peril. Overreliance on the screen image can (and often does) lead to late or missed focus-pulls.

There are a lot of things that go into being a good AC. Proper camera prep is still key as the AC must identify, scrutinize, and assess, every component in a camera package, from lenses and filters, to monitors, and every cable in between. This constellation of parts must fit and play well together, inclusive of the FIZ controller mapped to each lens.

Before digital rangefinders, many of the best ACs never even took out a tape measure. These skilled craftsmen, experts in their trade, performed brilliantly and accurately by keeping one hand on the camera’s FF while continually eyeing the action in front of them.

True, some ACs have the innate ability to judge distance, while others are more adept at finding and holding focus, but their timing is off. Ultimately, the best ACs anticipate an action or focus move, while delaying the focus move itself until the last possible instant, so as not to telegraph the action and undermine the story unfurling onscreen.

This is where the AC’s feeling for the story comes into play. It’s not enough to simply learn the mechanics of pulling focus by referencing the witness marks on a lens. The speed and timing of a focus move (like everything else in film and TV) are dictated by the story imperative. As the great American director Sidney Lumet so eloquently stated in his book Making Movies1: Story is the conduit through which all decisions flow. And that includes the speed and timing of shifting focus.

Accurate focus moves require a feeling for the story being told on screen. Assistant camera people should become familiar with the script or treatment to better anticipate and accommodate the action.

Accurate focus moves require a feeling for the story being told on screen. Assistant camera people should become familiar with the script or treatment to better anticipate and accommodate the action.

Some ACs may have trouble feeling the story imperative because they are not familiar with the treatment or the script, or they are simply too far from the camera. Working alongside the operator, the AC can more effectively anticipate the action by sighting along the lens axis while also receiving the occasional focus cue from the operator via a gentle prod, sigh, or wince. As COVID times may preclude such intimate interactions, all bets may be off for now. Even so, the operator can opt to communicate via a Tech-com headset, alerting the AC of potential focus issues in that way.

A good AC is a certain kind of person. A way of seeing the world. It’s much different than other disciplines on the set or in the camera department.

A good AC is a certain kind of person. A way of seeing the world. It’s much different than other disciplines on the set or in the camera department.

To today’s ACs, a high-resolution monitor offers significant advantages, like the ability to map one image atop another or view direct green-screen composites. Beyond this, by zeroing in on an actor in close up, the experienced AC, with superb timing and a clear feeling for the story, can very well anticipate and not lag behind the action, even when viewing the image in a monitor.


1  Making Movies (1996) by Sidney Lumet. New York, NY. Vantage Press.

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