Scientifically sound evidence for the flat earth

Ampersand

Edit: Didn't notice this was a Formali(ish) debate - my comment should be against.

A constant property of light is that it refracts - changing direction when it goes through a change in density gradient.



The atmosphere changes density the higher up you go - hence how people find it harder to breath at the top of tall mountains.

Ergo we would expect the atmosphere to constantly refract the light - albeit a very slight amount compared to the example above as the change in density is much more gradual. This causes objects to appear higher than they normally would - which can include being visible at all when they would be obscured by the Earth's curvature as from a persson's point of view all that matters is what angle the ray of light hits their eye at..



The curvature of light as it passes through a density gradient appears to be a universal constant that has been observed countless times, including in scientific experiments specifically looking at atmospheric refraction. You can catch the inference in the Op's own link where the photographer references "Refractive favorable circumstances".

Erfisflat

anonymousdebater said:

Fog or refraction can decrease or increase visibility.

Here are some pictures that show that the Earth is a globe: http://flatearthdeception.com/photos-prove-the-flat-earth-deception/

Fog or refraction can increase visibility. Agreed.



Visibility in our atmosplane is limited greatly. Heat, dust, fog, smog, smoke, pollen, dew, etc. etc. no doubt exist, this we know. You can check your local weather app for fairly accurate visibility numbers. 

 For a person about 6 feet, standing at sea level should see the end of their horizon at a mere 3 miles, according to the geometry of a ball with 25,000 miles. Boats should start going "over the curve", etc, etc. 

This "drop off" get exponentially larger, because the earth isn't a slope, so the further away an object gets, the drop off gets multiplied. An easy to remember formula gives us a good impression of how much curvature there should be, from sea level.

M^2 (8")   where m is the miles.

So 276 X 276 = 76,176 X 8 = 609,408"/12= 50,784 feet.

Samuel Rowbotham said it best:

"IF the earth is a globe, and is 25,000 English statute miles in circumference, the surface of all standing water must have a certain degree of convexity—every part must be an arc of a circle. From the summit of any such arc there will exist a curvature or declination of 8 inches in the first statute mile. In the second mile the fall will be 32 inches; in the third mile, 72 inches, or 6 feet, as shown in the following diagram:


For calculating exactly how much curvature there should be accounting for observer height, distance to the horizon, and the elevation of the object being viewed, there is a curvature calculator. 

https://dizzib.github.io/earth/curve-calc/

Refraction

For the first part, I'll take the few images that @anonymousdebater offered as evidence. The site offers pictures from inside various aircraft at various altitudes, and frankly, I don't trust any of them for the effects of refraction from warped glass that are in aircraft windows and camera lenses. 



It's basically impossible to get a line to stay straight consistently with curved glass. 

http://amp.travelandleisure.com/articles/why-are-airplane-windows-round?source=dam

http://epod.usra.edu/blog/2014/11/photographing-the-curvature-of-the-earth-trickier-than-you-think.html

The photos show horizons that vary with altitude from very slight curves at 40,000 feet to a substantial curve at 70,000 feet. However a balloon outfitted with one camera with a fisheye correction lens and one without shows a very pronounced flat line at 110,000 feet. 40,000 feet higher than any of the opposition. One may be able to even work out a slight curve from that somehow, but it is substantially less curved than even his highest camera, proving that curved glass of any sort will bend a line, and this evidence is at best inconclusive.




https://www.google.com/amp/s/amp.usatoday.com/amp/5165635

This refraction, or light bending brings us to our next counterargument against the OP.

But first...


A must in the scientific community is falsifiability.

https://explorable.com/falsifiability

In the globe model, and any other scientific theory, falsifiability would be a way to disprove that model. Ball earth proponents would have us believe that when their model has been falsified, another theory can be put forth to prop up the blatantly wrong, pseudoscientific model. 

The claim is basically an ad hoc assumption, which was made on another assumption (the ball earth theory). It sounds like a fairly plausible explanation, we all see how light can bend in various circumstances, in all manner of direction, depending on variables like how dense and rare mediums meet each other, and form a boundary to bend the light, where they meet. This all works, according to snells law.

https://en.m.wikipedia.org/wiki/Snell's_law

This formula gives us a great way to tell which direction the light will be bent. So let's have a look at the models, to see which direction the light should be bent, either up, or down, along with a practical experiment, which is rightfully so, the basis of the scientific method.

In the globe earth model, as my opponent explains, "The curvature of light as it passes through a density gradient appears to be a universal constant that has been observed countless times, including in scientific experiments specifically looking at atmospheric refraction."

When we look at snells law, we see that there is no mention of a density gradient. 

"Snell's law (also known as Snell–Descartes law and the law of refraction) is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media, such as water, glass, or air."

Basically, when light goes from a dense medium to a rare medium, the light is bent away from the normal, which is a perpendicular line extending through the boundary. When light passes through a rare medium to a dense medium the light will be bent toward the normal. This is displayed nicely in the opponent's image.


Reading over my opponent's claim, it isn't clear exactly where the boundary is, giving us no clue where the normal will be, but I'm guessing it is along the lines of this.


But these conditions would produce a superior mirage, as my opponent's link states, where a total internal reflection will occur, and the image would be inverted. Of course no inversion is seen in the OP image, and, being 9,000 feet in the air, it is probable that very little atmospheric refraction is occuring, if any at all, let alone 2 miles of earth dropping out of sight or a mountain being raised two miles high over that curve, all just to cause the earth to appear flat.


https://www.britannica.com/science/total-internal-reflection




http://www.physicsclassroom.com/class/refrn/Lesson-3/Total-Internal-Reflection

In both of the above images, the observer and observed are in the same medium, and a boundary is formed just above the observed. The angle at which the light is refracted is actually reflected, as per snells law, because the angle is a critical angle or better.



https://www.slideshare.net/mobile/mrtangextrahelp/06-partial-refraction-and-total-internal-reflection

Maybe in the coming rounds, instead of just asserting that refraction is the excuse we should believe, the opponents could do a better job proving that by defining the boundary, if i haven't done so correctly, so that we can see which direction the light is bent.

Consider what I propose now. It is known that dry air is more dense than moist air...

https://www.quora.com/How-dry-air-is-heavier-than-humid-air

...over some variable distance, depending on the temperature and density of the air, an accumulation of air causes a boundary to form between the observer and observed. The dryer air would be on top, causing the boundary to start forming higher up, and tilted downward, going further away, like this.



As you can see, the cat, were he flipped around to land on his feet, is seeing the fish in a lower position than his actual position. This fact has been demonstrated repeatedly, and the links are to actual experiments, unlike the opponent's link about mirages.









This shows unequivocally that if any refraction is occurring, it is not agreeable with the opponent's argument. 

someone234

I'm sorry but the truth will prevail.

Ampersand

I'll be responding to ErfIsFlat's points somewhat out of order as some of the responses to later points have a bearing on some of his claims in earlier points.

Snell's Law

As stated in my original post, light refracts based on changes in density in the medium through which it is passing. The earth's atmosphere grows less dense as you move further away from  earth causing refraction as the light travels through this.

ErfIsFlat does not dispute the core points, but instead tries to claim that this will refract based on Snell's Law. Snell's law is a real law and I advise you to take a look at his source for how Snells law works: https://en.m.wikipedia.org/wiki/Snell's_law

If you pay attention you can see the obvious problem in the very first sentence of the article - indeed the very same sentence that ErfisFlat quoted from and failed to understand. "Snell's law (also known as Snell–Descartes law and the law of refraction) is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media, such as water, glass, or air."

Isotropic media refers to a medium which is consistent in all directions and the boundary between the two is the place where they meet, e.g. the boundary between some moloecules of various gases comprising the standard expected in a ground level room and a plastic block as per my picture. The law is used in those instances. It is not used to calculate refraction through a single anisotropic media such as gas with small but constant variations in density. ErfIsFlat's own link and the very sentence he quoted explain this, but apparently he didn't have the comprehension to understand what is being said.

Therefore when ErfisFlat asks for the boundary of an anisotropic medium such as the atmosphere, it's like asking for the hypotenuse of a square so you can apply Pythagoras theorem to it to test whether squares are right angled. It won't work, but that's because Pythagoras's theorem applies specifically to right angled triangles - not all right-angled geometric shapes. Snells law is correct and works - but only in the specific conditions laid out not in every situation having anything to do with light refraction.

That ErfIsFlat manages to misread the most basic understanding of the law twice, including when he specificalyl copies and pastes it into his own post, is to me fairly incredible. Either it shows a massive issue of reading comprehension or it was a purposeful lie on the assumption that sounding like he knew what he was talking about would be enough and no-one would think to call him out on it. Even looking at it in the most favourable light, I think this shows that Erf is not competent to before analysis of even the most basic aspects of physics.

Snell's Law and Photos

Ironically, despite being completely useless in the manner that ErfisFlat tried to use it - Snells law is actually useful for a point Erf tries to hide from - photos of earth from high enough to observe curvature.

Every camera lense will suffer some sort fo distortion, not just fish eye lenses. this is as per snell's law. Different parts of the lense will be hit at different angles by light and therefore there will always be some refraction which in turn causes barrel distortion. This follows predictable parameters and the usual distortion will be as per the article I just linked and as per Snells law.

While ErfIsFlat tries to just wave away the entire argument with his argument that "I don't trust any of them for the effects of refraction from warped glass that are in aircraft windows and camera lenses." However as he admits later in the post, we know the law for what effects the refraction so this is something we can account for to work out how something actually looks.

Now the important thing to note is that as per the explanation of Snells law that ErfIsFlat himself has provided, the degree of refraction depends on the angle it hits the boundary at. Most notably and the easiest way for us to ascertain the truth, when it hits the lens dead on it doesn't distort.


With almost every lense people typically use you will therefore get distortion like the below:



You can see examples of this below with the earth seeming to change shape depending on whether it's above or below the centre of the lense:





Therefore all we need to do to ascertain if a weather balloon video shows if the earth is flat or not is pause the video while the balloon is high enough in the sky to see curvature and while the horizon is passing through the centre of the screen. At that point there will be no distortion so if the horizon is curved, that is because the earth is ca sphere. So what do we find when we actually do this?



We find that the horizon is curved and the Earth is a sphere. You can check this yourself with the original raw footage if you want: 



ErfIsFlat's hiding From the evidence.

Due to his disregard for how Snell's Law should be applied, ErfIsFlat ironically implies that I am just making stuff up as I am going along and that this doesn't meet the standards of scientific falsifiability.

For people who couldn't be bothered to follow a link, scientific falsifiability is a good thing and experiments should be falsifiable. In scientific terminology, falsifiable basically means "testable". There's no point claiming somethign is prove if you can't provide it, you should be able to conduct experiments which test whether it is true or false. of course if it is false then that's bad - but falsifiability only refers to the ability to test it. All theories which are falsifiable usually have been tested and proven correct or they would no longer be theories

He states: "In the globe model, and any other scientific theory, falsifiability would be a way to disprove that model. Ball earth proponents would have us believe that when their model has been falsified, another theory can be put forth to prop up the blatantly wrong, pseudoscientific model. The claim is basically an ad hoc assumption, which was made on another assumption (the ball earth theory)"

The problem is, the normal model of physics and the earth is falsifiable and it has been tested and found correct. Now as there are countless experiments both famous and mundane showing this. a few specifically dealing with refraction are below and the details can be found on all the main scientific journal portals:

Saastamoinen, J. "Contributions to the theory of atmospheric refraction." Bulletin Géodésique

Marini, John W., and C. W. Murray Jr. "Correction of laser range tracking data for atmospheric refraction at elevations above 10 degrees."

Mendes, V. B., et al. "Improved mapping functions for atmospheric refraction correction in SLR." Geophysical Research Letters 
Beutler, G., et al. "Atmospheric refraction and other important biases in GPS carrier phase observations." Atmospheric effects on geodetic space measurements, Monograph
Stone, Ronald C. "An accurate method for computing atmospheric refraction." Publications of the Astronomical Society of the Pacific
Westwater, W. E. AN ANALYSIS OF THE CORRECTION OF RANGE ERRORS DUE TO ATMOSPHERIC REFRACTION BY MICROWAVE RADIOMETRIC TECHNIQUES. No. ITSA-30. INSTITUTES FOR ENVIRONMENTAL RESEARCH BOULDER COLO
Arribas, S., et al. "Differential atmospheric refraction in integral-field spectroscopy: Effects and correction-Atmospheric refraction in IFS." Astronomy and Astrophysics Supplement Series 

ErfIsFlat tries to handwave away every single experiment ever conducted with a baseless and fallacious claim that "The claim is basically an ad hoc assumption, which was made on another assumption (the ball earth theory)." This is of course nonsense - if scientist's assumptions and theories were wrong, when they tested their theories they would not match the hypothesised result. Instead scientists using the normal understanding of the world constantly predict exactly how things will occur correctly. That this happens shows that the assumptions (e.g. the earth is round) must be correct. if it weren't round their hypotheses for the results of their experiment would end up being wrong when they conducted them. It is also why real scientists have produced mountains of evidence while flat earters have nothing equivalent on their side.

Mirages

ErfisFlat claims: "But these conditions would produce a superior mirage, as my opponent's link states, where a total internal reflection will occur, and the image would be inverted. Of course no inversion is seen in the OP image, and, being 9,000 feet in the air, it is probable that very little atmospheric refraction is occuring, if any at all, let alone 2 miles of earth dropping out of sight or a mountain being raised two miles high over that curve, all just to cause the earth to appear flat."

My link does not in fact state that. ErfisFlat never actually backs that up or provides a quote so he claim can be dismissed on that grounds alone, but lets absolutely demolish this claim. The writer provides a table where he lists the numbe rof images present in the refractive phenomenon and what happens:

https://aty.sdsu.edu/explain/atmos_refr/phenomena.html

Please note that he states you can observe the refractive phenomenon with only 1 image visible (e.g. the norm and completely separate from mirages with 2 or more images visible) which includes loomign and towering.

Looming is described as "When abnormal refraction increases the apparent elevation of distant objects — often lifting above the horizon things normally below it — the process is described as ‘looming.’. Because we associate a certain apparent altitude with a certain distance, this phenomenon generally makes the objects seem nearer than they really are."

Towering he provides an example that "shows almost uniform vertical stretching"

The writer even provides examples of the standard model as a seperate example from any kind of mirage where he clearly shows the path of the light curving with the earth, helping to see the object further away than would be the case if light travelled in a straight line as the atmosphere changes density

Once again ErfIsFlat has either suffered a horrendous failure of basic reading comprehension or is willing to lie and hope no-one bothers to double-check his claims. Either way, at this point I think no-one should take any of his claims at face value.

Erfisflat

Opponent 1 drops most of the points I made, and images from aircraft that he made.

"Response: In the flat Earth model, and any other scientific theory, falsifiability would be a way to disprove that model. Flat earth proponents would have us believe that when their model has been falsified, another theory can be put forth to prop up the blatantly wrong, pseudoscientific model."

Except I'm not offering another theory. I've offered a scientifically valid deconstruction of the claim, pointed out out just saying "refraction" is the epitome of pseudoscience invented to make excuses. I've offered verifiable demonstrations that support my points. All we have from the negative is "refraction" and "looming". You can't even explain in detail what looming is.

I have researched the phenomenon of looming. There is no supporting evidence for it outside computer models, but that particular type of refraction is claimed to be common in the lower atmosphere, where the atmosphere is relatively dense. Even the study that @Ampersand linked puts the observer height at under 2 meters.




Another quick look at looming gives a humorous description of looming:

"The visible effect is precisely the same as if the convexity of the surface of the earth were diminished.”

https://aty.sdsu.edu/bibliog/bibliog.html#Everett1874c

It was as if the experts were saying "since the earth is a sphere, refraction must be causing the curvature of the earth to relax, and reveal what is behind it." 

More than likely, the refraction that I showed with practical demonstrations and a reliable model as per snells law has relaxed, or the boundary has leveled out, and the light is travelling almost straight to the observer. With this science, we don't have to assume the impossible, that the water is humped in the middle.

Top reasons:

"1) Given spotlight sun, you would be able to see the sun from anywhere, just at an angle."

Why would a spotlight sun be a given? This is a strawman as this position isn't mine. The opponent is yet again assuming that light travels in a way that agrees with his model. I have presented experiments that show that the atmosphere causes a drop and magnification of distant objects like the sun. Once again, in case the opponent missed it.



"2) People in the North and South hemispheres see different stars."

This is due to a relatively low ceiling on the flat earth, and again refraction sinking those stars into the horizon/vanishing point. When one enters a large building, Even without walls and a higher ceiling, you see a different ceiling than if you were on the other side of it.

"Plus, if flat Earthers say that space pictures are faked, it would be just as reasonable to conclude that that picture was also faked."

Except the difference is verifiability. A very small percentage of humans have been to the alleged infinite vacuum of space. Literally anyone can go and witness the mountain peaks in the image I presented.

@ampersand , If you'll read that bold part once again, you'll see why Snells law is to be used instead of your pure assertions.

"Snell's law (also known as Snell–Descartes law and the law of refraction) is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media, such as water, glass, or air."

Con is attempting to discredit me with various ad hominem attacks, pretending as if I'm incompetent for assuming that air, and an accumulation of water in that air, can form what is known as a boundary. 

Con also offers no real explanation for his position. No mathematics, no model, and most importantly, no defined boundary. Just the appeal to the stone fallacy with an ignorant kicker, that he doesn't understand the concept that I present, though he doesn't have any ideas of his own. 

He drops a few links from different studies on refraction, but doesn't even try to explain any of them, instead insisting that I do his research for him. So were left with nothing. What if the atmosphere  (air) is an anisotropic medium? What does this prove? 

Snells law and photos

Con has graciously presented a 4 hour video of balloon footage with substantial curvature and an explanation of barrel distortion, much like the one I provided in previous round. The video features a convex earth a concave earth, and even a flat earth!




So my question is, why does he discard the normal camera footage that went to equal or better altitude that I presented in the previous round? Because it shows a flat horizon, which doesn't agree with his argument. He completely ignores that and posts a video that knowingly morphs the horizon. His claim that the center of the camera would not bend lines is nonsensical as cropping a video to offset the center is easy with any video editor. This makes this an inconclusive piece of evidence.

Fisheye lenses have the ability to curve a flat line, depending on the location in the lens I agree, but for a fisheye lens to make a curved line straight, the line would have to be at the very edge of the screen, as demonstrated here.



Making a curved line curve the other way would be impossible. This in and of itself proves that the horizon is flat, just as my video shows.

He goes on with more ad hominem attacks and some more links with no practical experiments or supporting evidence.

Ampersand

Snell's Law

ErfIsFlat doubles down on his claim that Snells law should be applied to atmospheric refraction - meaning there is no way his mistake can be a one-off slip-up and as explained in my previous post he truly must either have very fundamental issues with reading comprehension or is purposely lying to hopefully make it seem like he's got a point to voters who won't bother to read through the issue much.

Rationale 1

Even at the most basic level, the description which we have both agreed on is "Snell's law (also known as Snell–Descartes law and the law of refraction) is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media, such as water, glass, or air."

Now even putting in only the tiniest amount of intellectual effort into this; air and glass are two different media. Glass and water are two different media. Air and water are two different media. Air and air are not two different media.

The definition we have both agreed on specifically states it effects the boundary between two different media. Now as air and air and not two different media, ergo we would obviously not expect Snell's law to be applicable to atmospheric refraction. This is basic logic. Hell, I can literally even put it into syllogistic logical form if anyone wants as it, is an example of the modus calemes logical syllogistic argument form would be applicable.

I mean it's really incredible ErfIsFlat has doubled down on this.

Decription: "Hey, this calculation applies at the boundary between different mediums"
Erf: "Aha, this calculation obviously applies at places which aren't the boundary between different mediums"

His claim is literally the exact opposite of the definition he's accepted as correct, it's absurd!

Rationale 2

If you want to put a little more thought into it you can also look at the word isotropic. As explained before in my previous post with evidence isotropic refers to a medium which has consistent properties in all directions. I have already explained in my last post how this is not the case in the atmosphere and now ErfIsFlat has admitted that I was correct, stating in relation to looming that "that particular type of refraction is claimed to be common in the lower atmosphere, where the atmosphere is relatively dense". He admits the atmosphere has different properties in different places (denser lower down), therefore it is not isotropic (same in all directions).

There are two possible explanations for this:

1) Air can be considered isotropic when Snell's law is applied correctly because when you are looking at the change in density between two media (e.g. air and a black of plastic) you are only looking at the air as it borders the point where the media change. That it might be different a hundred metres away but that isn't a concern for your purposes.

When you try and use it incorrectly - to measure the change not at the boundary of two different media but over a long distance - you are now forced to consider not just one point where the air meets the other material but all throughout the miles and miles of air you're trying to addedd with all kinds of different densities due to pressure fronts, changes in density from height, different humidifies, etc. In that context it is no longer isotropic. This is what I believe to be the case and I could make a detailed argument to show this is the case, but as the only other option also benefits me there isn't much point in spending the time to do so when there is no possible way for my opponent to be correct.

2) The only other possible explanation is the definition that ErfIsFlat and myself are using is wrong and it does not explain how Snell's law should be applied. In that case we must discard Snells Law. As Snells Law was brought up by ErfIsFlat to try and give an alternate explanation for atmospheric refraction, this therefore leaves him bereft of scientifically backed points to counter atmospheric refractio.

Either option benefits my argument, although I hope readers will see how option 1 is the obvious actual answer if they took the time to read through the full original wiki page explaining Snell's law

ErfisFlat also does throw out other false or claims at me in relation to this which I'll cover off briefly.

"Just the appeal to the stone fallacy with an ignorant kicker, that he doesn't understand the concept that I present, though he doesn't have any ideas of his own."

An appeal to the stone fallacy refers it dismissing an opponent's argument as absurd rather than showing how he is wrong with engaging with the argument. I engaged with his argument and showed how it was wrong because it didn't meet his own definition for Snell's law and thus could not be true. Ergo ErfisFlat is making false claims which ignore the argument I actually made, then throwing random insults on there as well about me being ignorant and unable to present ideas of my own. This is a strawman fallacy as he is basing his argument on what he is imagining i said rather than what I actually said and ad hominem as he is merely insulting me, not coming to negative conclusions of me based on a reasoned argument.

"No mathematics, no model, and most importantly, no defined boundary."

First of all, this is hypocritical. I am relying on the same evidence as ErfIsFlat to prove my point in regard to Snell's law - we are agreed on using exactly the same sources and definitions. ErfIsFlat is using not an iota more proof than me because we are using the exactly same proof - yet he doesn't expect to have to provide these claims himself. This indicates a clear double standard where he expects not to have to reach the level of evidence that he asks everyone else to.

Secondly, this is illogical as he criticises be for not providing a defined boundary in relation to atmospheric refraction. Of course I haven't provided one because my entire point which I have logically explained is that no such boundary exists. ErfIsFlat is the one who says that this exists - so why is he unable to supply it and why is he asking me to make his argument for him?

"More than likely, the refraction that I showed with practical demonstrations and a reliable model as per snells law has relaxed, or the boundary has leveled out, and the light is travelling almost straight to the observer. With this science, we don't have to assume the impossible, that the water is humped in the middle."

His argument is that because he used showed that Snells law works appropriately in the conditions where it is meant to work (e.g. how it reflects light at the boundary between air and plastic or air and water) it should therefore work in conditions where Snells law explicitly doesn't work (air and air) - and he is fine just to make up reasons why this is the case rather than relying on evidence or logic. This is of course completely illogical as the one doesn't follow from the other.

Refraction

ErfIsFlat concedes the argument.

In R1 he was arguing that "But these conditions would produce a superior mirage, as my opponent's link states". In fact ErfIsFlat was making this claim up and the link specifically states that he was wrong and you would expect to see the expected increase in height in an image without it being a visible mirage. Being completely disprove and offers no rebuttal in R2 to my claim that he failed in terms of basic reading comprehension and was making up false claims.

Please also note that my evidence presented in R2 which clearly shows atmospheric refraction occurs without being a mirage and therefore explains the photos is from someone who ErfisFlat has stated he believes is "the world's leading experts on mirage". So to put it another way an expert source who ErfIsFlat has identified as the best in the world in this area states that the types of images ErfIsFlat brings up are just as we would expect on a curved earth with normal pyhsics and are NOT indications of a flat earh. 

Looming

ErfIsFlat claims "I have researched the phenomenon of looming. There is no supporting evidence for it outside computer models, but that particular type of refraction is claimed to be common in the lower atmosphere, where the atmosphere is relatively dense. Even the study that @Ampersand linked puts the observer height at under 2 meters."

So in summary ErfisFlat makes random claims supported by no evidence which in fact we know are wrong as actual evidence of looming and the atmospheric refraction causing it have been provided by those on the Against side (see my R2 argument). His argument can therefore be ignored as based on opinion only.

Lenses and Distortion

"Con has graciously presented a 4 hour video of balloon footage with substantial curvature and an explanation of barrel distortion, much like the one I provided in previous round. The video features a convex earth a concave earth, and even a flat earth!"

ErfIsFlat does not dispute that measuring the earth when it is in the centre of the screen (as I did and provided an example of) will show the Earth as it correctly looks. He then provides a video which supports my claims:



It explicitly states that images will distort as you move away from the centre of the image and will only remain in their actual shape while passing through the centre of the image. 

It doesn't matter how the image looks when it is distorted - I have already provided examples of images curving towards the edges of a camera picture - it matters how it looks when we know it is accurate. ErfIsFlats video confirms that we know it is accurate when it's in the centre of the lense. When it's in the centre of the lense, as shown in my screenshot and video last round is that the horizon is curved, ergo the Earth is curved and ErfisFlat's own evidence - which again he doesn't seem to have understood - supports this.

He also states: "a fisheye lens to make a curved line straight, the line would have to be at the very edge of the screen, as demonstrated here."

As per 1:37 on the video it actually states that it distorts especially at the edge of the screen, not only at the edge of the screen, getting more distortion as you get closer to the edge. Therefore how close to the edge you have to get to straighten a line will depend on how curved it is in the first instance. This is again exactly as per my round 2 description and images and completely contrary to ErfIsFlats claims which he seems to just be making up and hoping no-one checks the video.

He then states: "Making a curved line curve the other way would be impossible. This in and of itself proves that the horizon is flat, just as my video shows."

Again in what I can only chalk up to incredible stupidity or outright lying, Erfisflat again ignores his own evidence. His video clearly shows a curved line (a circular fan which is comparatively very curved, far more than we'd expect the earth to be from a weather balloon) being curved the other way.




The fan is clearly curving upwards as you would expect in the top image. In the bottom image it is clearly curving downwards; I've drawn a straight line between the two points it enters the screen to emphasise this. Ergo his claim that "Making a curved line curve the other way would be impossible" is clearly wrong and he would have realised this was the case if he'd bothered to look at the evidence. With a picture from in atmosphere we would expect the earth's horizon to only look a fraction as curved as that fan does (you'd have to go out into space to see the full circle of the earth) so it doesn't need to get as close to the edge to curve the other way.

At this stage with him even unable to analyse his own evidence correctly, I think there can be absolutely no trust in anything ErfIsFlat says.

He also asks a question: "So my question is, why does he discard the normal camera footage that went to equal or better altitude that I presented in the previous round? Because it shows a flat horizon, which doesn't agree with his argument."

I haven't discarded it. As per my statement the methods I employed can be used on any accurate relevant footage. I have provided evidence this is correct - my example in R2 - while ErfisFlat has provided no evidence whatsoever opposed to this. He merely claims that his footage shows a flat horizon but offers absolutely nothing to support this. As I have provided evidence in R2 and he is just making baseless claims, his claim can be ignored. Even though I don't need to as there is no evidence contradicting my position, just empty claims, I probably would have gone the extra mile and used his video as an example but I took a quick look and the image quality is so poor I can't even tell where the earth ends and the sky begins, although if you check it out you can see the upper atmosphere where it starts to darken is clearly curving in line with the earth.

It ErfisFlat wants to provide proof to counter the evidence I brought forward in R2 he is welcome too, but empty claims shouldn't be given any credence.

Falsifiability

ErfisFlat claimed the spherical earth and refraction in particular isn't falsifiably tested - e.g. scientists haven't actually conducted experiments to show that is true or false. That seems a mindbogglingly incredible claim which he in no way backed up with any evidence, again completely baseless and ignoring examples even children know about Like rockets into space where we have literally taken pictures of a round earth, but even then I provided several links to scientific studies to show that this was flase

ErfIsFlat now argues: "He drops a few links from different studies on refraction, but doesn't even try to explain any of them, instead insisting that I do his research for him.

This shows that ErfIsFlat has no point and is just scrambling for excuses to avoid engaging with arguements - likely because as shown he is completely incapable of doing so. When you make an argument he complains that scientific studies back it up. When you present scientific studies he then complains that you are not presenting a personal argument. He cannot just continually change his mind about what form of argument he wants, changing his mind as soon as he is presented with exactly what he asked for.

Summary

Pro has completely failed to make a case for proof of the earth being flat. He is so poor at looking at evidence, not seeming to watch his own videos or understand sentences he quotes, that is stretches credibility that this is down to ignorance alone rather than a desire to be proven right even if it means lying. With this in mind his argument has quickly reverted to baseless and empty claims, his arguments fundamentally relying on "because I say so" rather than any evidence or reason.

The argument centres around whether taking a picture showing a mountain that's further away than you would expect to be able to see on a spherical earth where light travels in a straight line through the atmosphere shows that the earth is flat. The answer as has been explained is no, because we live on a spherical earth where light refracts across a density gradient including in the atmosphere and therefore the photos are consistent with what we'd expect to see on a spherical earth and therefore support that conclusion.

Erfisflat

The image you provided is a highly cropped, misleading image. 



The colors have obviously been obscured, due to it being a picture of a television, the horizon is clearly seen. The image can be explained with Snells law, exactly as my model shows. A line can be drawn closer to the observer, when the boundary starts, this in combination with what is generally seen with distance, foginess, for lack of a better word, as seen in round 1.


 The light from the sky has been lowered. The ship isn't higher. 

These types of images have even been logically explained by the guys at metabunk, where they've been asserted as "fata morgana", an equally wrong term for that type of image.



https://www.express.co.uk/news/weird/679359/FIRST-FLOATING-CITIES-Now-phantom-flying-boat-could-have-emerged-through-portal

https://www.metabunk.org/debunked-fata-morgana-hovering-boat-mirages.t9112/

"You say that you aren't offering another theory, but you are saying that this picture supports the flat earth theory."

Yes, since we've never seen the entire earth at one time,  we can only theorize on whether it is flat or a ball, based on evidence. The ball earth proponents here have posited a theory to explain the image, and I have cut out the guesswork, and have shown with science, math and experimental evidence that the theory is false. The only rebuttal we have from the negative is more assertions. 

"For me personally (if anyone wants to, say something), I have never been in a building where I could see the ceiling in every direction, yet see entirely different things than somebody on the other side of the room."

Maybe a visual will help.


A person standing at one end of the hallway will not look up and see the same tiles as someone on the other end. Those tiles have blended in with the horizon. With refraction, those stars remain relatively the same size, due to the magnification, and lower, as experimental data shows, so they melt into the horizon at a faster rate. This is due to the dome in the flat earth model, containing a liquid.

http://lmgtfy.com/?t=v&q=stars+p900


"And you can't just say "fisheye lens - debunk". See https://flatearth.ws/fisheye"

I'm not exactly sure what debate you're referring to, as I've never said that quote. If you'll read the posts above, I've given meticulous explanations as to why I don't accept images as conclusive evidence for a curved horizon, and explained that the "line crossing the center" argument is inconclusive also. There is a cropping feature that can offset and change where the center actually is. 


"Finally, you can do a Pinchusion distortion to make a curved line straight."

As we can plainly see, this is irrelevant, as the two types of lenses are seperate, and no pincushion type lens has been prevented. My quote was:


"for a fisheye lens to make a curved line straight, the line would have to be at the very edge of the screen"

And of course @ampersand posts his response in the middle of the night with only 3 hours to respond, two and a half hours of those are used for sleep. It's 7:00 am, and I'll throw out some quick responses to his late entry.

Air and water are two different media. The water in the air, as I explained, accumulates over distance. This is logical. This is science. It can be explained as if you were in air, the rarer medium, looking out into a plastic block, if you will, as the opponent explains as isotropic medium, causing refraction.

The opponent points again to the experts on mirage who assume the earth is a sphere for us. For a university to openly claim the earth is flat, and the altitude is too high for refraction to have any bearing would have lost their merit, as this is taboo.

The opponent again wishes the readers to ignore my arguments, while putting forth little effort to explain or show how refraction is working in his favor.


He continues on with more claims of "stupidity or lying" about the fisheye lens video he presents, ignoring any possibility that it was cropped, and continuing to disregard the video I presented in R1. that reached 2,000 feet higher, 110,000 feet.



Which again shows a flat horizon, where the opponents video, that warps the horizon, shows a substantial amount. He claims I've conceded, but these are his dropped points.

He now asserts that scientists have proved the spherical earth by sending rockets into space to photograph it, but as anyone knows, those images are all computer generated.

https://www.nasa.gov/centers/goddard/about/people/RSimmon.html

"The last time anyone took a photograph from above low Earth orbit that showed an entire hemisphere (one side of a globe) was in 1972 during Apollo 17"

The rockets are sent out to sea.


...and the images are faked.



Edit: time stamp 32:00
(The entire video is worth watching, but not all is relevant to the point)



out of time unfortunately