Even more maps, with a twist

In this opening view from this video here, doesn't the Grand Canyon appear inverted to you? As in the deep parts pop up instead of down!

click to enlarge 

Well, following on this post here, I referred to a LinkedIn article here, where I explain at the bottom how to make relief appear the right side up:

In order to see the topography "right side up", I posted the map picture upside down & copied source text over: it's a trick to work around the optical illusion that appears to reverse map relief; see Topography & Geomorphology halfway down Poster Catalog blog.

This article in the Guardian here, moreover, prompted me to revisit that trick. It appears that artists used it also for an entirely different purpose. They ask:

Is it a bald elderly man with a big bushy beard and a wine-addled stare? Or a friendly young woman with flowing locks and a crown of braids?

screen capture from article above

So, here is what happens if you do the same in my map illustration mentioned atop:

click to enlarge

At left with North at the top, the oceans in tan appear to pop up from the landmass in purple. Turning the image upside-down at right restores the oceans as appearing to be basins below the land mass.

Check also this story map here, for a more complete explanation about field mapping forty years ago (emphasis added here):

1 - Early days

This is what started it, a social media post on stereo viewing. Be it in university field school in Alberta or Ontario CAN, or field work in the Rocky Mountains or Arctic Islands described next, I worked on stereo airphoto pairs... anyone remember those? I had to force my brain to make topography show high points up*. The trick? Do away with stereo lenses and make yourself look way past the photo toward an imaginary horizon, then your eyes remove parallax and restore the 3D view and right-side-up relief.[...]

*: it's an optical illusion that relief appears inverted unless it's  lit from the NW . And since most landscape is lit from the South in the Northern hemisphere, air photo and satellite imagery are prone to such 'inversion'.