ATLANTA — Charles Moore was a news photographer who became a photojournalist and died a visual journalist — not because he changed, but because the technology, nomenclature and just about everything else involving his profession did.

Shooting first for Montgomery newspapers in his home state of Alabama, then more famously for Life magazine, Mr. Moore was probably the most influential of a battalion of still photographers who swept across the South to capture, with compelling clarity, the dramatic collision of massive and passive resistance, black and white, right and wrong.

Mr. Moore raced on foot to scenes, sometimes with the camera already at his eye, often with his feet moving backward. Relying mostly on short-range lenses, he moved closer to the action than any photographer, began shooting, then moved even closer.

The television medium was barely 15 years old, and large-format magazines were wildly popular, when Life devoted 13 pages to photos by Mr. Moore, Flip Schulke and others at the University of Mississippi showdown in 1962, then 11 pages to the deployment of dogs and fire hoses in Birmingham the next year.

The unsettling images from civil rights battlegrounds, followed closely by the disturbing images from Vietnam battlefields by Horst Faas, Eddie Adams, Nick Ut and others, created a golden era for photojournalism.

Today, everyone with a cellphone is a photographer/videographer and streaming video has become a national obsession. But has the proliferation of images devalued photojournalism and dulled its influence?

As director of multimedia for MSNBC.com, Stokes Young sees phenomenal still images and videos running across his screen from across the world. He can quickly reel off a dozen names of photographers producing riveting work that provokes strong reactions.

The economic crisis has undermined the quantity of photographers in the print media, especially among local newspapers in the United States, but “the quality of work at the top end of photojournalism is astounding,” he said.

Meanwhile, the surge in the number of photos and videos from nonprofessionals gives news outlets more eyes on news. Editors are busier than ever sorting through citizen offerings of earthquakes, tornadoes, riots and, of course, dogs dressed up for St. Patrick’s Day, and then confirming the veracity of those from politicized situations.

“In the diffuse media landscape it is much harder for any particular image, much less a piece of serious photojournalism, to command the consciousness of a nation or the world,” Mr. Young said.

But, he added, “the nonprofessional picture increasingly has the possibility of punching through to center stage.”

That’s what happened last year when Neda Agha Soltan, an antigovernment protester in Tehran, was shot and killed. Her death was captured in a cellphone video that spread quickly through the digital world. A close-up “screen grab” of her bloody face, plucked from the video as a still, was soon distributed, an excision that has become journalistically more acceptable with improvements in the quality of videography.

There is concern among many professionals that the journalistic standards of the golden era aren’t being handed down. For decades, photographers would cram into workshops and conferences where Mr. Moore, Mr. Adams, Mr. Ut and others would discuss the important values of their craft. Those courses have been replaced by Webinars.

Still, at many new-media Web sites that accentuate photojournalism, the social awareness that guided Charles Moore endures. “Documenting social injustice is the cornerstone of our profession” and remains a powerful motivating force in photojournalism, said Brian Storm, founder of MediaStorm.org, which this year became the first Web recipient of the Alfred I. duPont-Columbia University Awards for broadcast journalism.

As a constant reminder, Mr. Storm need only look at a wall in his Brooklyn office, where he has placed an 11-by-14-inch black-and-white photograph from Birmingham showing a black woman and two black men pounded and pinned to a storefront wall by a fire hose’s white laser stream. The picture was taken by Charles Moore.