An echo is a good way to describe the photogram, which is a visual echo of the real object. That's why I like to work with the photogram, because the contact with what is represented is actual. It's as if the border between the world and the print is osmotic.
Deep into that darkness peering, long I stood there wondering, fearing, Doubting, dreaming dreams no mortals ever dared to dream before; But the silence was unbroken, and the stillness gave no token, And the only word there spoken was the whispered word, "Lenore?" This I whispered, and an echo murmured back the word, "Lenore!" — Merely this, and nothing more