I love this thread, I really do. It does show the intelligence level of people on this site, or lack there of. Especially I love the photo provided showing in incandescent bulb lighting a small portion of a wall.....
LOL... what I find more than funny is that the flat earthers invariably say that all photographic images from NASA or high-altitude aircraft or satellites are bogus, and can't be used as valid evidence in support of a spherical planet. But in the next breath, they expect us to accept that any/all of the photos the FEs post are legitimate, and should be accepted as honest evidence for whatever they're claiming—like the light-bulb photo. Pot, meet kettle.
LOL......What I find more than funny is this whole thing about the sun.
But seriously.......from a flat earther's viewpoint, that is.:
The sun "acts like a spotlight and shines directly down on the earth."
There must be some kind of a reflector (like in a flashlight) or some kind of shade (like in a ceiling light) to shape the lighting pattern of the sun into that oval or circular beam as shown in the animation.
The sun must be just inside, under the dome.
There must be some kind of a light track or some way to guide the sun in its orbit....or several tracks for different seasons.
And it looks as if Greenland is in the sunlight, 24 hours per day, 365/366 days per year.(From the animation.)
At least that is the way I see it.
......Until a flat earther has a better explanation.
But since the sun only shines down on the earth, how the moon and the planets are illuminated is another subject for discussion.

Are there Marsshramps, Venusshramps, etc. besides Moonshramps ?