I'm not certain but I think the idea was also fomented in one of the old Sinbad movies (the mythical sailor, not that idiot actor). A few of the shadows on the closer shells are a little sharp on the edges but, overall--and from the perspective of someone who has helped create a number of undersea paleontological panoramas for museum exhibits--you did very well.
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The reflections on the bottle, surface of the ocean, bubbles, lightbeams, and color variations on the shells are especially skillful.
Really wonderful work! And fun!! It would make a great desktop.