Sometimes it seems as though photography has eaten the rest of the art world. A century ago, using a camera was fundamentally distinct from painting, sculpting and performing. Nowadays, photography has crept across the borders of all three of those disciplines, becoming a broad, promiscuous uber-medium.

Regardless of whether they identify themselves as photographers, many artists use cameras to document their performances, site-specific sculptures and sociological experiments for gallery audiences. Further, some artists copy, combine and reprint other people’s photos at will to make new pieces. So, if art is being made somewhere, a camera is probably involved, or maybe a photograph the artist has found or taken.

This sudden explosion of the medium makes summing up the last half-century of photography difficult. Still, the Baltimore Museum of Art is willing to give it a shot. For its current show, “Seeing Now,” curator Kristen Hileman draws from the museum’s substantial and varied collection of photo-related artworks to give an encyclopedic overview of what has happened in photography since 1960.

In one room, you’ll find gelatin silver prints of performance artist Vito Acconci in 1970, naked and furiously biting his legs. In another, you’ll see Edward Burtynsky’s large-scale digital print depicting an Australian landscape destroyed by mining operations in 2007. And in yet another, you can see Andres Serrano’s “Black Supper,” a group of photos taken in 1990 for which the artist spray-painted tiny figurines representing Christ and the apostles and submerged them in soda water.

With indelible images such as these, “Seeing Now” demonstrates that the BMA has been collecting edgy, challenging, up-to-the-minute work. That said, the show has problems, many of them stemming from the sheer quantity and variety that Hileman has grouped under one big, unwieldy umbrella.

Hileman jams 200 works into galleries that could probably house about half that number comfortably. Because there are so many styles in the mix, Hileman doesn’t split hairs. Instead, she opts to group works under general categories such as “Seeing People,” “Seeing Places” and “Seeing Pictures,” which means chronologies and chains of influence get lost in the shuffle.

Take, for example, two groupings of gelatin silver prints hung across from each other in a somewhat narrow gallery space. A cluster of 18 photos from photographer Danny Lyon’s 1971 book, “Conversations With the Dead,” showing men in prison serving long sentences, hangs directly across from 14 images from Garry Winogrand’s 1975 book, “Women Are Beautiful,” a voyeuristic project mostly depicting emancipated ladies partying.

It’s a jarring juxtaposition — the prisoners are sometimes half-clad and look vulnerable, but across from the partying women the pictures look as if they are part of a sensuous fashion spread. And that distracts from the main purpose of Lyon’s book: empathetic engagement with society’s doomed elements.

Winogrand was a traditional street photographer, stealing glimpses of his subjects through wide-angle lenses. Lyon was aligned with New Journalism: He immersed himself in the lifestyles of the people he photographed, spending time with them, gaining their trust and ultimately involving them in the process of making his pictures. It’s an important distinction. Yet in proximity to larger, later works in color and paired under the none-too-elucidating label “Seeing People,” the actual content of these two very different bodies of work is obscured.

The show also fails to differentiate full-time photographers such as Winogrand or Lyon from moonlighting artists. Take Mickalene Thomas’s re-imagining of Edouard Manet’s landmark 19th-century painting “Le dejeuner sur l’herbe,” for example. In her photo, Thomas has replaced the nude and partly nude women entertaining a group of bohemian men in Manet’s piece with a trio of physically strong African American women, projecting confidence with their glistening skin, retro attire and commanding postures, gazing directly at the viewer.

Yet Thomas is primarily a painter, known for creating glossy, colorful portraits with enamel, acrylics and rhinestones. In fact, this photo became the basis for a monumental painting installed last year in the 53rd Street window of the Museum of Modern Art in New York.

The photo is certainly strong enough to work on its own. But its marginal position relative to the rest of the artist’s output is at least worth noting and could have provided an opportunity to explore how photography has proliferated in all kinds of art careers.

One suspects the show was designed as a sampler platter for the uninitiated. Yet the crowded groupings, lack of context and even the inclusion of fairly disturbing images — say, for example, Larry Clark’s 1960s pics of naked teens and pregnant women shooting drugs — seem more likely to turn off visitors lacking a baseline understanding and an appetite for weirdness.

Overall, “Seeing Now” reveals that the BMA has some great stuff in its vaults. Just don’t expect the exhibition’s organization — or lack thereof — to offer new insights into why people do what they do with cameras.

Cudlin in a freelance writer.

“Seeing Now:Photography Since 1960”

Through May 15 at the Baltimore Museum of Art, 10 Art Museum Dr., Baltimore. More information at www.artbma.org.