Center on Contemporary Art, 728-1980. Through April 8.

Performing Photography
Henry Art Gallery, 543-2280. Through June 3.

Culture Shock: The Photography of John Gutmann
Henry Art Gallery, 543-2280. Through May 27.

Some arguments should die when their time is up, such as the conversation about photography and its relationship to Truth. Haven't we all accepted that a photo no longer constitutes proof, that its authority has gone the way of Photoshop? As far back as the '70s, Susan Sontag declared, "The disconcerting ease with which photographs can be taken, the inevitable even when inadvertent authority of the results, suggest a very tenuous relation to knowing."

I think that the folks at CoCA are aware that this kind of discussion is on the downslide, and that's why they've couched Indexterity in such belabored terms. The show takes its underlying principle, as well as its title, from the study of semiotics, minutely laid out in the press release (available for you to read at the exhibition). In it, we are treated to a mini-lesson on signifier and signified, the terms used by the likes of Barthes and Saussure to discuss how we relate what we perceive to what we know. When in doubt, you know, obfuscate.

I'm not sure that a press release is the best place to begin this kind of education--intellectual cachet of the terms notwithstanding--and the exhibition suffers from a similar kind of overweening attention. Curator Daniel Kany has chosen five artists whose work he has arranged in what curators call "conversations": By contrasting black and white with color, artifice with naturalness, the staged with (what we assume is) the real, the show aims to inspire discussion.

There is nothing wrong with this premise, as overworked as it is. There is certainly something provocative about, for example, the work of Yauger Yauger, who manipulates images of Minimalist masterpieces and presents them as saturated, barely translucent Lucite objects, occasionally with little cartoons cavorting across the surface. Throw such work next to the studied realism of Deborah Coito's black-and-white prints, and you do have to wonder about what technology has wrought, how we got from documentation to such intense manipulation. But Kany seems to have determined already what these conversations should sound like; the works are clustered so close to each other they act as a map of his intended argument. Obviously, when you put a Coito image of a slightly odd and perhaps retarded man next to Miguel Edwards' blurred, densely colored Shiva (her many arms and pendulous breasts created by multiple exposures), you're going to think about various degrees of staged reality, about the impact of color, the restraint of black and white. Obviously, a Yauger in close proximity to (Ms.) Timothy Ringsmuth's text, photo, and mirror installation speaks to different levels of abstraction and distortion. The arrangements seem too prescribed, just too manipulative for the show's own good.

And the work itself isn't quite interesting enough to sustain the conversations that Kany seems to have in mind (with the possible exception of Yauger). Coito's work depends on the sweet and provocative combination that Sally Mann has made her signature; Edwards' images reminded me of New Age goddess posters; and Ringsmuth's work just seemed out of place--more about installation than photography.

At the Henry, Michael van Horn succeeds in making a more pointed argument in Performing Photography by selecting works that document artists' performances. Such photographs are often the only proof that a performance happened at all, and sometimes they are the whole point (such as the time Vito Acconci walked through Greenwich Village and took a picture every time he blinked). So, assuming that everyone is clear on just how staged the event was, we can begin a more relevant discussion about contemporary photography, which concerns the various levels of art and conceptual success it does or does not achieve. There's also Culture Shock, an exhibition of work by John Gutmann, a German immigrant whose pictures of American life from the '30s, '40s, and '50s show us just how strange this country looked to an outsider; the scenes he recorded seem strange to us not because he manipulated them, but simply because they were strange to him. The issue is not photography's relationship to the truth, but the photographer's relationship to the thing photographed. Which, I hope, will put this tired old question to rest.