Long ago, before the euro and the internet, I was a young backpacker on my first trip to Greece. Beaches were broad and unpeopled. I traveled on boats to islands large and small, always noticing the tiniest ones jutting from the Aegean like beacons or sculptures. In the midst of youthful island-hopping, the romance of the Aegean and the Mediterranean—their mythologies and histories—caught me. German-Greek artist Christina Dimitriadis—whom I met years later and whose art and life has taught me much about what one could call the contemporary Greek condition—takes the act of moving between isles as the most direct point of departure for her photography exhibition “Island Hoping,” curated by art historian Denys Zacharopoulos. The notion is embedded in the punny title (I’ll get to the “hoping” part in a moment). But like any of Greece’s 6,000-odd islands, this show possesses multiple layers and approaches. Along the far wall of the white, windowless exhibition space are 30 photographs (all 60 by 90 centimeters and collectively titled “Island Hoping”). Each depicts an island or group of islands too small for human habitation rising from the sea, centered in the frame. The images share a horizon line where water meets sky, just below …