Say “cheese,” and that’s often the result: A cheesy, plastered-on fake grin in a photo. Dean Fleischer-Camp, who directs the popular “Marcel the Shell With Shoes On” videos with former “Saturday Night Live” comedian Jenny Slate, pranks his friends by asking them to pose for photos, but taking video of them instead.

As a prank, it’s amusing, but as a look at what people do to pose for a photograph — the artifice, the forced stillness, the authenticity of a smile fading with each second that passes — it’s a fascinating study. It shows us how much posing for a photo brings us out of a moment and makes us vulnerable. Gawker wrote in a headline yesterday that it “inadvertently makes profound statement about the brevity of happiness,” as the subjects try to put their best face forward for the snapshots. It also wouldn’t be possible without modern cameras and camera phones, which make it difficult for the subject to know whether they’re being photographed or videotaped.

Fleisher-Camp’s video is reminiscent of Andy Warhol’s “Screen Tests” series of films in which he would invite Factory regulars, or just people he thought exhibited “star potential” to sit for a film portrait. The subject would stay as still as possible, often staring directly into the camera. Warhol made about 500 of these films, some featuring celebrities like Susan Sontag and Lou Reed.