In one of the Flattards' YT vids I've seen which prattles on about 'perspective'...
The example is used of aircraft and their contrails. Those nicely straight ones are certainly suggestive to the eye. But! The whole *critically* crucial matter of perspective acceleration is omitted. Those planes, on their essentially constant-altitude/constant-speed paths appear to very significantly speed up and then slow down as they cross the sky, having a maximum angular velocity when the ground track is nearest the observer.
The Sun, however, maintains always a virtually constant angular velocity from sunrise through sunset. Anyone can measure this, and compare the vast rate difference in behavior with objects like planes. Even satellites evince perspective acceleration almost as strongly as do planes. (For satellites, their higher altitude results in us seeing them track through a larger arc over the curved Earth, the result being a slightly smaller rate of change in p.e. at given angular altitude, and more so nearer to the horizon.)
Another piece of crap example. The bigger Sun as seen from higher elevations (meaning you're closer to it), based on *overexposed* video images which bloom the Sun to many times its actual diameter. Moreover, whatever image scale differences between video clips are unknown to start with, nor the degree of overexposure of the Sun.
If a mountaintop view resulted in a sensibly larger Sun, then why the hell does not the Sun vary in its apparent diameter during the course of the day? If the Sun maintains a constant height above the flat Earth, and said distance is less than the Earth's diameter, the hen we should see the Sun vary in diameter by easily a factor of two. Again, visual observation of the filtered Sun through a telescope never shows other than a fixed angular diameter.
So, the the matter of perspective acceleration and a varying solar disk size are conveniently overlooked in their 'model.'
And of course, the very fact of the Sun intercepting the horizon at the *same angular velocity* as when transiting the meridian is a killer fly in their ointment. Not to mention that a Sun supposedly always some thousands of miles above the disk could ever be seen to plunge to a sea level horizon in the first place!
If their argument is to be atmospheric refraction, then the obvious counter is the appearance of the constellations, which are seen to not be meaningfully altered by such an effect. The star patterns remain sensibly fixed, wheeling about at the same (essentially, for our purposes, neglecting the Sun's eastward movement against the sidereal universe) constant angular velocity as the Sun.
These yokels who confidently crow about their limited, untested observations 'proving' the Earth's flatness only reveal their utter ignorance of basic science. This topic matters to me because my beloved sister believes this *****, among much other woo.
