MIAMI — Whirr doesn’t mix well with “Medicare-for-all!”

That’s what some photojournalists learned at NBC’s Democratic debate on Wednesday night. As noted previously in this space, this “pool” of mainstream-media shutterbugs — from the Associated Press, Agence France-Presse, Reuters, Getty, the New York Times, NBC and the Miami Herald — shot the debate from a perch on the second level of the Knight Concert Hall of the Adrienne Arsht Center for the Performing Arts of Miami-Dade County.

However, the photojournalists requested at least momentary access to the side of the debate stage, where they could capture photos of the candidates stacked sideways. NBC agreed to the request, though it spotted a slight problem with the arrangement.

When a first set of photojournalists started taking their close-up photos, an NBC producer picked up on the whirring sound of the cameras. A directive was quickly relayed: No shooting unless it coincided with audience applause, the better to drown out the din of the digital single-lens reflex (DSLR) technology that has been screwing up audio feeds for years and years. Shutters on DSLR cameras include moving parts — including a mirror — that make a flap-click sound when they are activated.

As this blog reported last year, Times photographer Doug Mills and other Beltway photojournalists started using the Sony A9 camera, puncturing decades of dominance by Nikon and Canon. The A9 is a mirrorless apparatus that makes no sound. It came in handy for Mills on Wednesday night. He was in the second shift that was allowed close to the stage. “When I got there,” recalls Mills, “the woman who was from NBC said, ‘Hey, you can’t shoot.’ I explained to her my camera was mirrorless and she was like, ‘Why doesn’t everybody have one of these?’ So then I just kept shooting.”

“I had a great advantage,” says Mills.

For Thursday night’s event, says Mills, one of the other photojournalists in the group was planning to use a “sound blimp,” which is essentially a camera muffler.

The concerns of NBC, moreover, are legitimate and have roots in decades of sneering between TV/radio people and still photographers at major news events. Clackety camera mirrors commonly corrupt audio feeds, and incidents such as the one on Wednesday night should accelerate their extinction.

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