Nautilus 69, photo by Harold Davis. View this image larger.

This is a photograph of a mildly Photoshopped nautilus shell combined with a rotated version of itself.

The mild Photoshopping consists of blending the original with a LAB color inversion of itself using the Multiply blending mode at a low opacity and a layer mask (created as described here) to eliminate the black background of the inversion.

I have a feeling that I’m going to be photographing this nautilus some more!