You wouldn’t guess it by looking at them, but Antonia Macedo’s photographs don’t rely on click-of-the-mouse wizardry to craft their unreal, highly suffused reds, yellows, and oranges. Macedo simply uses time-tested tricks of the trade: lens filters, in-camera double exposures, and the printing of a single image from two separate slides. All the more reason, then, to marvel at her finished products, now on display at Touchstone Gallery. Macedo’s figurative photos depict piers, boathouses, shacks, and clapboard houses, each made eerie not just by their respective color schemes, but also by the images—which range from rock surfaces to wooden exterior walls—superimposed upon them. The impressive Flicker of Light, for instance, modifies a calm image of a whitewashed church by overlaying a stuccolike texture that causes the resulting image to mimic the surface of van Gogh’s Starry Night. The artist’s more abstract photographs—which marry the aesthetics of graffiti photographer Aaron Siskind with the color palette and geometric orientation of the drip-painter Morris Louis—are just as well done. Also on view are two photographic series by Carolyn Johnson: One is a fitfully successful exploration of colored lights (pictured), the other a travelogue of the familiar beige adobe walls of the American Southwest. The latter comes close to equalling Johnson’s similarly themed study of Greek architecture (published several years ago as the book Light Forms), but here, it’s the exposed timbering that steals the show, casting unexpectedly bold shadows on the smooth wall surfaces. The exhibitions are on view from 11 a.m. to 5 p.m. Wednesday to Friday and from noon to 5 p.m. Saturday and Sunday, to Sunday, Oct. 3, at Touchstone Gallery, 406 7th St. NW. Free. (202) 347-2787. (Louis Jacobson)