Faking It: Manipulated Photography Before Photoshop” is one of the most compelling photographic exhibits to hit D.C. in years. It aims to encapsulate more than 150 years of photographs that were deliberately engineered to advance a goal: to improve technical limitations of the medium, for instance, or to convince the viewer of political perspectives, express an artistic vision, or simply to have fun.

Some early efforts at manipulation look clumsy to the modern eye, but then again, early viewers were often unsophisticated about how images are constructed; consider an oval-shaped image (middle) in which the artist combined the cropped heads of dozens of prominent citizens in 1850s Scotland. Today, it’s an obvious pastiche, but the piece prompted one viewer at the time to ask when and how the photographer managed to get everyone to pose at the same time.

Still, as inelegant as some of these manipulations were, others prove strikingly persuasive, even eerily modern, such as a colorized 1880s image of an old-fashioned French clock (bottom). In this exhibit, pictorialist efforts—-like Edward

Steichen’s lovely, color-saturated moonrise over a woodland pond (top)—-age better than a surprisingly bland selection of 1920s and 1930s avant-garde works. The selection of kitschy novelty photographs, a mainstay for decades, is a mixed bag, with some patently ridiculous but others unexpectedly authentic-looking, such as a “man in a bottle” and a decapitated subject holding his own head.

A series of Soviet-era images in which comrades of Stalin disappear with each photographic iteration is chilling (as well as a terrific example of forensic photo history); the same technique of erasure is put to more creditable use in the works of Kathy Grove, who carefully excises women from classic photographs as a feminist statement. The exhibit’s captions are usually informative but are sometimes hard to read due to their background; unfortunately, the exhibit pares down the number of images from its prior run at the Metropolitan Museum of

Art. (Mystifyingly, it also ignores the post-Photoshop era almost entirely.)

On the upside, though, the catalogue is superb, with a panoply of additional images and commentary. Ultimately, what viewers of this varied and thoughtful exhibit take home is the realization of how special photography is. Because no other artistic medium carries such a promise of factual accuracy, manipulation is never more powerful—-or produces a deeper kick to the gut—-as when it involves a photograph.

Through May 5 at the National Gallery of Art, 4th Street and Constitution Avenue NW.