One of the most compelling evidences of Flat Earth is how far we can see with our own eyes, yet ALL Globe believers are in complete denial about it. The problem for the Globe believers is that we can see much further than we should be able to if the Earth was a Globe. The alleged curvature of a Globe Earth would mean many things we can see should be beyond the curve, yet they are not. The problem (until recently) for Flat Earth believers, is that Globe Earth believers need us to present repeatable evidence to prove what everyone can actually see with their own eyes. I personally find this hilarious but it is what it is... or was.
There are several issues to overcome for repeatable tests. For example, curvature vs. flat tests need to be carried over water to ensure origin and target points are at the same height over a 'level' surface (water always finds its own level). However, tests during daylight can be impacted by refraction and atmospheric conditions. The time-lapse video below (originally posted on YouTube by Mark Sergeant) shows an example of this. You can observe the water levels rising up and down and even the land compressing and decompressing yet the camera is fixed throughout.
To counter this, many have used laser tests over water (and even across iced over lakes) at nighttime. These tests have been ignored/discounted by the Globe believers as they say they weren't independently observed. It wouldn't matter what test was carried out, Globe believers would find a way to convince themselves the results were not possible and faked.
That was until someone used an infrared filter on a camera during daylight. Such a filter cuts through much of the atmospheric smog and pollution to reveal the truth. The Earth IS Flat!
The video below shows a simple test across Salton Sea. Team A is on one beach with a large mirror to reflect sunlight 8 miles across Salton Sea to another team who are filming on cameras with infrared filters. If the Earth was a Globe, the results shown in the video would not be possible as the teams should be hidden from each other by 36 feet of curvature (accounting for refraction).
I used the Salton Sea test above as it an easily repeatable test.
One of the main YouTube contributors of Infrared Flat Earth videos is a channel called 'JTolen Media 1'. I have added one of their videos below that includes clear explanation of what you are viewing. They have several videos like this that showing just how flat the earth is.
A final point on this though is that when presented with evidence like this, most Globe believers turn straight to insults. They cannot provide any intelligent counter. My wife Desideria has the best response to them. She asks them just one question...
'Please explain to me for what, on any given day, would you or I have to account for the Earth's spin or curvature?'
No-one has been able to answer this with anything but the easily debunked Coriolis effect. Try it yourself :)