3 ms·

Since the reflected points emanate from the (curved) scratches themselves, I would think that between the left and right eyes, each point would be slightly vert

Since the reflected points emanate from the (curved) scratches themselves, I would think that between the left and right eyes, each point would be slightly vertically misaligned (since each eye would see light from a different vertical point in each scratch, beside a different horizontal point). I suppose you could eliminate this by drawing the scratches as if they were cross-sections of a Fresnel lens: i.e., at several points during the scratch, reposition the compass fulcrum vertically so that the needle remains at approximately the same vertical location.

wbeaty 11y ago
See 3.4 in the paper, http://amasci.com/amateur/hand1.html#34 http://amasci.com/amateur/hand1.html#34 also figure 11b. Yes, a proper "abrasion hologram" would have holo-pixels resembling little fresnel-lens cross-sections. The "hand drawn" version is simplified, and produces weird artifacts unless viewed perpendicular, and the reproduced image isn't too wide. Yet even so, we can create a 3D object in less than an hour via simple hand-scribed circles on soft plastic. Use an architect compass and an old CD case. It's now appearing on vinyl, on Jack White Lazaretto album, also on recent re-release of classic 1976 "Rush 2112"... https://www.youtube.com/watch?v=H9gRPtkSOn0 https://www.youtube.com/watch?v=H9gRPtkSOn0 https://www.youtube.com/watch?v=jqNF9IWmFQE https://www.youtube.com/watch?v=jqNF9IWmFQE Find lots at https://www.youtube.com/playlist?list=PL60100E8F3572CEB1 https://www.youtube.com/playlist?list=PL60100E8F3572CEB1