Thank you for the references! It's good to have more precise ways of talking about the drop in acuity.

Yes, "blurry" is a vague term. To do all of vision in 2 paragraphs, some things get glossed over.

Sorry I hit an optic nerve. ;-)

Yes!

And if you have ever seen a skink/chameleon/lizard bounce up and down (looks like doing pushups), they are doing the same thing that we do with our two eyes. They move their head to two different positions, and use the paralax to figure out what is in the 'depth' dimension. (Some people also say that they do this in courtship or for displays of dominance, which could also be true.)

It's like the GIFs that alternate between two perspectives to show depth, like this

To understand the way they "see" things, you can re-frame what you think eyes "do."

Eyes take what is in the world and translate it into something the brain can understand. Chameleons probably perceive the world just as the world is--their brain makes a map of what is 'out there' based on the light that falls on their eyes.

By the way, you own eyes do the same thing. You don't see the "input" to your eyes. You see the map of the world that your brain makes from the input. For example, you don't "see" your nose, even though it takes up a bunch of visual space in each of your eyes' visual input. (Close one eye and look for your nose to check!)

You also don't see details in the world except for a tiny fraction of your vision (the "fovea" in the center of your visual field). Want to check: hold your hand out at arms length and look at your fingernail and without moving your eyes, try and describe any detail on one of your other fingernails. You will likely discover that you can't. You cant even see details a few inches from what you are looking at. Whenever you look at something, you are looking with your fovea. Everything else outside of the fovea is "blurry" and much less colored. You mind fills in the blanks and you end up perceiving the world as clear an detailed.