A camera lens is a portal, a sort of window onto moments that can be self-evident or enigmatic. For “Reflection Unknown,” Fred Zafran pointed his camera at openings, whether actual or figurative. The Multiple Exposures Gallery show is “an allegory of doubt and inquiry,” according to the photographer’s statement.

The most expected subjects are windows and doors, literal portals that become metaphors for discovery, transition and hidden depths. Zafran’s color pictures, many of which are overwhelmingly black, gaze into unknown interiors. In one photo, there’s someone on the other side of the glass, peering outward through a bank of curtained windows. More characteristic is a picture of a person at an entrance, a moment rendered in a whoosh of motion that supplies a sci- fi feel. A simple step through a doorway appears to be occurring in hyperdrive.

Not all of Zafran’s subjects are literally enterable. He also portrays shadows, lights, mist and bodies of water, from puddles to oceans. The liquid is reflective, like glass, but trickier. One picture of the moon over the sea depicts the natural satellite — also a reflector of light — and two white patches on the surface below. The three small, illuminated areas are openings in the darkness, but they aren’t actually entrances. Zafran shows us visual paradoxes: things that appearpermeable but actually offer no way in.

Fred Zafran: Reflection Unknown Through Nov. 19 at Multiple Exposures Gallery, Torpedo Factory, 105 N. Union St., Alexandria. multipleexposuresgallery.com. 703-683-2205.