Thanks @adrian2301I was hoping it would be something like this, but I’m afraid it ain’t that simple;
When the eyeball in the photo were about 24mm, then that would mean, that we’d be looking at about half the eyeball and the eyelids would be something like this:

And the fact that the ruler is closer to the camera works against you:

I just noticed that the ruler I drew is actually 2 m, but that is not important, you get the idea…