Not sure how anyone could view this video and not see the obvious is beyond me. With the observer's eye-level around 10, (or more), feet above the water-line, the distant shore line is clearly obscured by the convex surface of the water. In fact, at around 11:10 of the video, distant boats on the water are far above the bases of the buildings even more distant.
Then -- with conclusive proof to the contrary, the videographer proclaims that "the Earth is flat, Jack". Remarkable.
The actual, visible curvature in the Earth is a function of distance and the observer's height of eye level. At 24,901 miles circumference at Earth's equator, any object would have to be 69 miles distant to demonstrate a 1 degree tilt away from the observer's eyes at 6 ft above the water's surface -- however -- at that distance, the object would be over 3,000 feet below the observer's horizon. (360 degrees into 24,901 = 69.17 miles). Then: 69 X 69 X 8 divided by 12 = 3174 feet.
In addition, light, especially over great distance and over water, tends to refract downward, skewing, (sometimes profoundly), visual results depending on a variety of atmospheric conditions.
The "tilt" of an object away from the observer will never be observable, even with an observation point of great height -- from an airliner, for instance. Discerning a 1 degree tilt/slant at 69 miles distance is impossible for obvious reasons.
Considering matters of refraction that can vary quite a bit, I believe the best way to observe and clearly demonstrate the Earth's curvature is to observe a large ship headed for open ocean, on a clear day. Viewing from a multi-storied structure with an unobstructed view of the ship's path is ideal. A decent telescope with tripod is very helpful.
From the ground floor, wait to observe the departing ship to reach the horizon. The ship will eventually begin to go past and behind the visible horizon and seem to slowly "sink" as the hull is more and more blocked from view. As the ship's distance grows, only the uppermost parts of the ship will be visible -- and eventually the entire ship will descend completely from view.
Move to the upper floors of the structure, (the higher, the better), and refocus the telescope. Even with the expected atmospheric distortion at a great distance, the ship's upper portions will be back in view. A ten story, (or more), structure is ideal, as an observation at ground level, the fifth story and finally from the tenth story would offer dramatic and unmistakable results.