Editing Multistable perception (section)

=== Real-world phenomena ===
Photographs of craters, from either the moon or other planets including our own, can exhibit this phenomenon. Craters in stereo vision, such as our eyes, normally appear concave. However, in monocular presentations, such as photographs, the elimination of our depth perception causes multistable perception, which can cause the craters to look like plateaus rather than pits. For humans, the "default" interpretation comes from an assumption of [[top-left lighting]], so that rotating the image by 180 degrees can cause the perception to suddenly switch.<ref>{{cite web |title=A lunar illusion you'll flip over |url=https://www.discovermagazine.com/the-sciences/a-lunar-illusion-youll-flip-over |website=Discover Magazine |language=en}}</ref><ref>{{cite web |author1=Minutephysics |title=The "Mountain Or Valley?" Illusion |url=https://www.youtube.com/watch?v=V7C318DGB38  |archive-url=https://ghostarchive.org/varchive/youtube/20211212/V7C318DGB38| archive-date=2021-12-12 |url-status=live|website=YouTube |date=29 June 2017}}{{cbignore}}</ref> This phenomenon is called the concave/convex, or simply up/down, ambiguity, and it confuses [[computer vision]] as well.<ref>{{cite book |doi=10.3217/978-3-85125-603-1-13 |year=2018 |last1=Breuß |first1=Michael |last2=Mansouri |first2=Ashkan |last3=Cunningham |first3=Douglas |chapter=The Convex-Concave Ambiguity in Perspective Shape from Shading |title=Proceedings of the OAGM Workshop 2018 |isbn=978-3-85125-603-1 }}</ref>