In general, we at the Flat Earth Society do not lend much credibility to photographic evidence. It is too easily manipulated and altered. Many of the videos posted here to "prove a round earth" by showing curvature will show no curvature or even concave curvature at parts. The sources are so inaccurate it's difficult to build an argument on them in either case. Furthermore, barrel distortion and other quirks of modern cameras will cause a picture to distort in ways which may not be immediately obvious or apparent, especially without references within the picture. Photographs are also prone to distortion when taken through the bent glass of a pressurized cabin as well as atmospheric conditions on the outside. With this litany of problems, it's easy to see why photographic evidence is not to be trusted.
41.) When astronomers assert that it is "necessary" to make "allowance for curvature" in canal construction, it is, of course, in order that, in their idea, a level cutting may be had, for the water. How flagrantly, then, do they contradict themselves when the curved surface of the Earth is a "true level!" What more can they want for a canal than a true level? Since they contradict themselves in such an elementary point as this, it is an evidence that the whole thing is a delusion, and we have a proof that the Earth is not a globe.

Regarding the "traveling at the same speed" idea. When in an aircraft, two people can toss a ball to each other. From the POV of those Inside, the ball is moving at normal ball tossing speed. From the POV of those outside, the ball is being gently tossed to over 500kph and the catcher catchers it without problem. If this is the "everything on the planet moving at the same speed" idea in action. Which does make it possible to travel in either direction.

“hundred miles below the sun and moon, [then it] cannot, by any known possibility come between them. It cannot therefore intercept the light of the sun, and throw its own shadow upon the moon. If such a thing were a natural possibility, how could the moon continue to shine during the whole or any considerable part of the period of its passage through the dark shadow of the earth? Refraction, or what has been called “Earth light,” will not aid in the explanation; because the light of the moon is at such times “like the glowing heat of firer tinged with deep red.” “Reddish is not the word to express it, it was red–red hot.” “The reddish light made it, seem to be on fire.” “It looked like a fire smouldering in its ashes.” “Its tint was that of red-hot copper.” The sun light is of an entirely different colour to that of the eclipsed moon; and it is contrary to known optical principles to say that light when refracted or reflected, or both simultaneously, is thereby changed in colour. If a light of a given colour is seen through a great depth of a comparatively dense medium, as the sun is often seen in winter through the fog and vapour of the atmosphere, it appears of a different colour, and generally of such as that which the moon so often gives during a total eclipse; but a shadow cannot produce any such effect, as it is, in fact, not an entity at all, but simply the absence of light.

We have abundance of evidence that the Sun moves daily round and over the Earth in circles concentric with the northern region over which hangs the North Star; but, since the theory of the Earth being a globe is necessarily connected with the theory of its motion round the Sun in a yearly orbit, it falls to the ground when we bring forward the evidence of which we speak, and, in so doing, forms a proof that the Earth is not a globe.

29. If the Earth were a globe, it would, unquestionably, have the same general characteristics - no matter its size - as a small globe that may be stood upon the table. As the small globe has top, bottom, and sides, so must also the large one - no matter how large it be. But, as the Earth, which is "supposed" to be a large globe, bas no sides or bottom as the small globe has, the conclusion is irresistible that it is a proof that the Earth is not a globe.
Some say the flood was a myth. But there is plenty of evidence of Noah’s flood to prove that it really happened. If you believe in the story of the flood in the Bible, then you must also believe in the “waters above” that God used to destroy that wicked generation. The only Earth model that fits the Biblical description of a glass firmament, holding the waters above, is the Flat Earth. Again the globe falls flat!

Always keep in mind that tangible science is a flat earth, a ball dangling in the sky is science fiction or Hollywood. I believe the firmament to be an ice dome, described to be glass. The hotter we make the "planet" the more that dome melts, I believe the salt beds are salt dropped out of the sky as water evaporated to become air. Gods rendition is tangible science.
50.) We read in the inspired book, or collection of books, called THE BIBLE, nothing at all about the Earth being a globe or a planet, from beginning to end, but hundreds of allusions there are in its pages which could not be made if the Earth were a globe, and which are, therefore, said by the astronomer to be absurd and contrary to what he knows to be true! This is the groundwork of modern infidelity. But, since every one of many, many allusions to the Earth and the heavenly bodies in the Scriptures can be demonstrated to be absolutely true to nature, and we read of the Earth being "stretched out" "above the waters," as "standing in the water and out of the water," of its being "established that it cannot be moved," we have a store from which to take all the proofs we need, but we will just put down one proof – the Scriptural proof – that Earth is not a globe.

95) On a clear day from the highland near Douglas Harbor on the Isle of Man, the whole length of the coast of North Wales is often plainly visible to the naked eye. From the Point of Ayr at the mouth of the River Dee to Holyhead comprises a 50 mile stretch which has also been repeatedly found to be perfectly horizontal. If the Earth actually had curvature of 8 inches per mile squared, as NASA and modern astronomy claim, the 50 mile length of Welsh coast seen along the horizon in Liverpool Bay would have to decline from the center-point an easily detectable 416 feet on each side!
78) From Anchorage, Alaska at an elevation of 102 feet, on clear days Mount Foraker can be seen with the naked eye 120 miles away. If Earth were a ball 25,000 miles in circumference, Mount Foraker’s 17,400 summit should be leaning back away from the observer covered by 7,719 feet of curved Earth. In reality, however, the entire mountain can be quite easily seen standing straight from base to summit.