In the history of motion-picture technology, few operators have had a more profound effect on camera movement than Garrett Brown. While dollies and cranes were Hollywood’s go-to platforms into the late ’60s, Brown’s ingenious camera rig — dubbed the Pole and later renamed Steadicam — started a photographic breakthrough that’s still growing 50 years later.

Preceding the prototype’s successful debut in 1972 for ABC Sports (covering female jockey Robyn Smith on a 600-foot uncut walk from weighing room to paddock), Brown sent out an “impossible shots” reel that included a scene of his girlfriend and future wife Ellen ascending the 72 steps at the entrance of the Philadelphia Museum of Art with, miraculously, nary a camera wobble.

One of the people who saw that reel included director John Avildsen, and sure enough Brown’s invention landed three colossal projects in 1975 alone: Avildsen’s “Rocky,” Hal Ashby’s “Bound for Glory” and John Schlesinger’s “Marathon Man.”

On “Bound for Glory,” where he was hired by cinematographer Haskell Wexler, the six-foot-five-inch Brown stood atop a Chapman crane three stories high, with the picture’s Stockton, Calif., migrant camp and sprawling mass of 900 costumed extras waiting below. Feeling nervous anticipation at his first time on the set of a major motion picture, he trembled during rehearsal before the shot. “Your hands are shaking,” fellow operator Donald Thorin observed, “but not the camera!”

Slowly descending on the crane while filming the scene, Brown transitioned off the platform with one flowing step at ground level, continuing his unbroken coverage of lead actor David Carradine’s stroll across the shantytown. An artful mix of fluid operation and framing, Brown’s three, 4-minute-long takes received a standing ovation in dailies. Moving-shot parameters were changed forever.

Then came “Rocky” and Sylvester Stallone’s iconic run up the steps where Brown had filmed his future wife. Brown’s footage established a new movie location for cinephiles that’s still drawing fan visits to this day. For the escape-sequence shots of Dustin Hoffman running in “Marathon Man,” he traversed the Brooklyn Bridge numerous times on night exteriors, demonstrating his new rig’s ability to handle difficult coverage.

The camera operator worked on more than a dozen movies that hit theaters in 1980-81. One of the calls came from Stanley Kubrick, who, when he saw Brown’s original demo reel, wrote to him that the invention “will revolutionize how films are shot.” The promise was realized on “The Shining,” where Brown made the fast-moving tricycle runs of child actor Danny Lloyd a horror classic. “Stanley provided the choreography for the move,” says Brown, “and I did the dance.”

Steadicam works with a low-friction gimbal combined with a counterweighted post and articulated arm connected to a rigid vest worn by the operator. The device provides a camera person zero center-of-gravity functionality and shake-free coverage with nearly every moving shot.

Now 76 yet hardly retired, Brown continues to invent. His newest Steadicam innovation (with engineer Steve Wagner) is the M1 Volt. Employing a push-button, gyro-integrated microprocessor and driven by brushless motors, it enables automatic horizon leveling while framing.

Referring to operating the Steadicam, the Academy Award-winning inventor offered an analogy. “It’s like painting while riding a horse,” says Brown. “One’s artistic, the other physical — but together, they take you to a place.”