@sceptimatic
I dig it! If I understand you properly, your contention is that with the horizon dead center and level/horizontal through your lens(es) ("horizon drop" and elevation are irrelevant / red herring) - as you zoom in, assuming a sphere earth, the horizon should ultimately disappear as you zoom "beyond" the "physical point" of the horizon (into "empty space"/sky).
The fact that this doesn't happen (the horizon remains a fixed horizontal, never curving, line dividing the lenses as it did initially, until you zoom so far that it all hazes out due to interaction with air/matter) suggest that the plane continues as far as the eye can see, even aided.
@JackBlack
Does the above make sense to you? The "horizon drop" is irrelevant.
No, that does not match what he is saying.
He is saying that if Earth is round, if you merely looked out towards the horizon, you would not see it at all and instead would see nothing but sky, which is completely false.
He is saying that the fact you see the horizon at all, instead of nothing but sky indicates Earth is flat, which again is completely false.
He refuses to provide any justification at all for this at all, other than basically repeating his claim and saying Earth curves down.
He refuses to acknowledge that for a RE, the horizon, when viewed from near sea level, will be basically the same as eye level, with it only a tiny bit below.
He refuses to acknowledge that all measurements have some uncertainty and that an observation of a horizon appearing at roughly eye level, does not actually show that it is exactly at eye level and instead allows it to be slightly above or below.
And that also means the horizon drop is extremely relevant.
If your measurement can only tell if the horizon is within a degree of level, and the RE should have it a mere 2.4 arc seconds below level, then you cannot tell the difference. You observation matches the RE.
So your claim that it is irrelevant does not make any sense at all, especially with the evidence which shows the horizon is below eye level.
That also means the last part isn't a fact either. The fact is that the horizon is observed to be below eye level.
And no, typically the horizon does not haze out due to light passing through the air. Typically by the time that is an issue you are high enough to see it clearly below level (and the fact that it is observed to be below eye-level is irrefutable, backed up by mountains of evidence and with no objection other than dismissing it as fake).
Instead, what typically makes it blurry is a limitation of the optics used.
For me the best piece of evidence glaringly absent from the "empirical science" of the globe model is the empirical measurement of the (fictional) curvature of water's surface at rest.
Do you mean the very real observations and measurements?
A simple qualitative one is an observation of a distant object which is above the water level, with you also above the water level.
Somehow the bottom of the object is obstructed, as if the water has curved to block the view.
Or do you mean at the small scale, where it is observed to curve at the edge of a container?
Water does not curve at rest, and cannot due to its fundamental behavior
What fundamental behaviour would that be? Do you mean how it adopts a level surface to minimise energy?
Noting that "level" is fundamentally distinct from "flat"?
Such that due to gravity, and Earth's rotation it adopts a roughly oblate spheroid shape, just as observed in reality?
in the sustained convex manner the globe model requires, no one has EVER measured that to be the case
You mean no one has ever measured it to not be the case.
I am yet to see a single actual measurement of the surface of water at rest which indicates it does not curve to follow Earth.
water's surface is always level/horizontal and flat at rest (which is a natural law of hydrostatics that has stood unchallenged for centuries).
Pure nonsense.
While you are correct that it remains level, that is not horizontal, nor is it flat.
All it takes is a simple observation of water in a thin tube, where it curves at the edge to see that.
Another observation you can do is look a droplet of water on a waxy surface.
Notice how it isn't flat?
It has been centuries since capillary action was first recorded.
Likewise, it has been known that Earth is curved, and that water follows this curve for centuries.
And both of these have stood unchallenged for centuries. (and no, people just dismissing it isn't actually challenging it, challenging it would be providing evidence which shows it is false)
There is no law of hydrostatics which demands that water remains flat or horizontal.
Then rejoice! You have that "big sign"! The horizon is an optical illusion, the edge of nothing but our vision, and does not curve at any altitude.
What causes this magical limit to our vision?
Why can we see past it, rather than objects disappearing from vision as soon as they cross that threshold, rather than disappearing from the bottom up?
How does this magically lower objects, such that it appears that the bottom is obscured by the water? Why don't we just get a region of darkness instead?
Why does the distance to it vary depending on altitude?
Why doesn't the distance to it vary depend on optics used to measure it?
And that still isn't observing Earth to be flat. Observing Earth to be flat would be seeing all the way to the edge.
For example, when I look at a flat table, from above, I can see all the way to the edge of the table, seeing basically everything on it.
But with Earth, instead of seeing that, we can only see a small portion, with that matching what you would expect for a RE.
As for the curvature you think you witnessed, there are several possibilities :
The simplest, and most likely of which is that Earth is in fact round.
Meanwhile, the alleged flatness you think you have observed is due to the curvature being in a direction which is intrinsically difficult to actually observe, and due to just how small the curvature is.