[gadf]

I don't think those papers mean what you think they mean. I could be wrong, I'm not perception studies expert, but the first one seems to say that binocular parallax (signals from looking with two eyes) are relatively reliable, especially in daylight conditions (the case you critique). Second two seems to talk about how high up in the sky something is as being the biggest distortion in estimating distance. Also the last one involved bizarre artificial conditions of looking through light bending prisms. Our eyes are definitely unreliable (to a certain extent), you have a blindspot in the middle of your vision in both eyes (retinal optic nerve spot) but you nearly never see it because your brain can interpolate. But I think judging something like this, in the well lit conditions described, I think you're exaggerating the difficulty. And I dislike that because it seems dishonest, and cruel to witnesses. It's a form of gaslighting. You have people (Navy pilots, civilians) coming forward and seeing things, and then everyone else wants to say, "Are you sure you saw that?" I get it, because you didn't see it, so it's natural to doubt. But you will walk across the street today, and reach down and pick up a coin, and I'll stop you and say, are you sure those cars are that far away, are you sure you see the coin. Don't cross the street, don't touch that coin. Maybe it's a hallucination. Maybe it's a bomb. Maybe it's a snake. Of course I wouldn't do that. That would be crazy. People casting doubt should doubt their own doubt too. It shouldn't be natural to doubt when so many people say the same thing.