Glenn Maxwell vividly recalls the only whale-watching cruise he ever took, two years ago off Puerto Vallarta. As waves rocked the boat, he says, scores of the giant mammals leapt clear of the water. Alas, Maxwell's memories of his Mexican adventure are better than his snapshots. Knowing a photo opportunity when he saw one, the Detroit computer programmer took dozens of pictures with his $500 Olympus digital camera. But each time he pressed the button, the camera paused, the whale flopped back in the ocean, and, Maxwell says, "I only got sky or sea."