Sometimes the eye can be fooled by perspective.
I live on the side of a big hill, with a steeply sloping field at the side of my house. I once saw what my eye perceived to be as a gigantic black cat stalking through the grass towards sheep, at a distance of a few hundred metres in that field.
It was only upon steady watching of the ABC that it was revealed to be an ordinary moggy (and one of MINE, even worse!) but a fold in the ground made tens of metres look like a couple of hundred metres. So my eye was fooled by the perspective into thinking that a much closer ordinary sized cat was a much further away very big cat. The fold was a small, narrow one that looked like a much bigger valley.
Here I pause for a moment for us all to quote Father Ted. ("These are small, those are far away...")