Five years ago, Emily May started up Holla Back New York City as a “little blog” for friends to share their experiences with sexual harassment on the streets of New York. Back then, May was hard-pressed to find who agreed that those “hey babies” and “nice asses” constituted a legitimate form of harassment. “I was getting street harassed three or four times a day and I felt like I didn’t have an adequate response,” May says. But within six months of the blog’s launch, victims of street harassment from around the world had joined May in hollering back online. “I never expected to strike such a nerve,” says May.

“Hollering back” implies a verbal response to street harassment, but May and co. have always considered the blog a visual medium: Part of the therapeutic effect comes from actually photographing the creep. “We encourage it. It’s kind of our model,” May says. “It feels a lot more fierce and bad-ass and validating to take a picture.” The blog is regularly peppered with shots taken at the scene of the harassment, featuring logo-emblazoned delivery trucks, blurry license plates, and slumped-over Subway riders.

Photography-as-activism was “always the original intent” of Hollaback, says May. “That was the classic Hollaback: To take a picture of what happened. It was never intended to be a mugshot—-you could take a picture of his shoes, or you could wait until he was a few blocks away and he was a tiny dot on the camera—-but the idea was to respond in the moment and capture some essence of the harassment.”

But when local activists Shannon Lynberg and Chai Shenoy mounted a D.C. branch of the Hollaback movement last March, they found that local harassees were a bit more reluctant to whip out the camera phone. On Holla Back DC!, locals regularly write lengthy retorts to the strangers who harass them on the street, but don’t usually accompany the prose with a visual.

Why are District holla-backers more shutter-shy? Perhaps it’s as simple as a branding issue. Holla Back New York City’s main page features a line of New Yorkers holding their open cell phones menacingly toward the camera. Holla Back DC!’s more textual approach doesn’t aggressively encourage the harassed to snap a pic in the moment, but it does provide the multimedia option on its submission form page. In lieu of user-submitted photos, Lynberg and Shenoy often accompany anonymous posts with stock images from Flickr.

But the local reluctance to broadcast visual evidence of incidents that often aren’t quite crimes also illuminates a rift in activism styles between D.C. and New York. “D.C. is a much smaller place,” Lynberg hypothesizes. “Someone knows someone who will know someone that knows the perpetrator in the picture. And that breeds fear. . . . people are more afraid of litigation here.” According to May, to-shoot-or-not-to-shoot is a highly personal consideration, regardless of locale: “We know that in a lot of situations, people aren’t comfortable taking a picture of the harasser,” May says. “It’s not appropriate for every situation, and it’s up to the individual to decide if it’s appropriate or not.”

Perhaps individuals in D.C. are more likely to decide that snapping a photo of a stranger isn’t appropriate—-or perhaps they just need a little encouragement. This month, May plans to launch a new iPhone app that she hopes will facilitate both photo- and text-based holler backs around the world. Meahwhile, Holla Back DC! is working to address street harassment through less confrontational methods —-the group is working on a public mural in Columbia Heights, is raising money to start up a “RightRides” program to help women and LGBT people travel safely through the city at night, and is planning “town halls” to engage directly with community members on the issue. The blog also maintains a Google map to chart incidents of street harassment around the city, a technological feature the founders hope will encourage solidarity against street harassment, and help victims “find courage and strength to report their incident,” if they so choose.

“Activism [is still] different in D.C. than it is in New York City, but that’s changing,” Lynberg says. Case in point: Last month, a Holla Back DC! photograph helped police identify a serial harasser who was groping and photographing women at the Courthouse Metro station.