# The Flat Earth Society

## Flat Earth Discussion Boards => Flat Earth Media => Topic started by: TomInAustin on September 08, 2020, 08:27:15 PM

Title: How High Do You Have To Be To See The Curvature?
Post by: TomInAustin on September 08, 2020, 08:27:15 PM

The guy that did this video is very educated about physics.   This video is NOT presented to try and prove flat vs round but is a great explanation of the question.  Its also an entertaining one as it allows you to pan and tilt around.

Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Dr David Thork on September 08, 2020, 08:30:50 PM
I'd recommend at least 2 grams of coke. 😵
Flat Earth humour is just on another plane.

Minimum settings 60,000 ft ... but 80,000+ ft recommended.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Tumeni on September 20, 2020, 02:20:56 PM
Simple geometry could tell us. Taking the Red Bull Space Dive of a few years ago as an example, climb to a certain height above the Earth's surface. Application of spherical geometry and trig, combined with the textbook figures for radius/diameter/circumference of Earth will tell you how far you will be able to see to the horizon, and what landmarks or geographical features you will be able to see within and at that distance.

The type of camera optics used does not enter into the discussion. Fisheye, telephoto - whatever, does not matter.

Apply this to the Red Bull flight, and it yields, at the stated height of the capsule, a visibility splay of approximately this size;

(https://i.imgur.com/6DSiiG2.jpg)

Note that no large body of water is expected to be seen with this splay, and none is seen in the video or photos from the capsule. Compare the video and photos to a map of the area within, and it can be seen that the capsule can "see" only the approximate area shown, and has no visibility beyond. Entirely consistent with a sphere/globe Earth.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: jack44556677 on September 27, 2020, 04:01:22 AM
Thork beat me to it.

You have to be REALLY, REALLY high.  Like never coming down, never gonna be the same, kind of high.  LSD is the "space age" drug of choice, and one of the only ones strong enough to induce the kind of hallucination you are after.

There is no curvature of the horizon at any attainable height.  This has been confirmed to the nth degree, and you are welcome to confirm it for yourself for around \$100 if you want.

The horizon is an optical illusion, the "edge" of nothing but our vision, and we were all egregiously mistaught about it.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: AllAroundTheWorld on September 27, 2020, 07:44:04 AM
There is no curvature of the horizon at any attainable height.  This has been confirmed to the nth degree
So are all the high altitude photos showing curvature fake or distorted?

Quote
The horizon is an optical illusion, the "edge" of nothing but our vision

If that is true why can we see things beyond the horizon but not all of them? Why do things sink below the horizon as they get further away. If it’s the limit of our vision shouldn’t they just vanish?
And why does horizon distance increase with height? Why does the limit of our vision increase when you ascend?
These things make sense in the context of a globe, what is your explanation?
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: jack44556677 on September 27, 2020, 11:23:12 AM
Quote
So are all the high altitude photos showing curvature fake or distorted?

Yes.  They are all distorted, though "faked" is most often/likely not accurate.  There is no perfect lens, and no lens designed and calibrated to do what we are trying to.

Quote
If that is true why can we see things beyond the horizon but not all of them?

Because of diff/refraction, reflection, absorption/emission, and the omnipresent attenuation of light.  The farthest you can see, even aided, horizontally while standing anywhere on earth is around 200 miles.  Light doesn't travel forever.

Quote
Why do things sink below the horizon as they get further away.

They don't.  If you are careful with your observations you can observe that the receding object shrinks with the expected perspective, but the height of the ship never changes/lowers.  The illusion of the disappearance starts from the bottom up, and it has to do with the densest air interacting with the light nearest to the water and angular resolution.  The light from the bottom of the boat is the first that is unable to reach the distant observer (or be resolved) anymore.

Quote
f it’s the limit of our vision shouldn’t they just vanish?

There are more optical effects taking place.  They should "fade"/"haze" out, which they do - and the known density gradient means the fading out should happen by the bottom first typically.  Also the density gradient bends the light, so the light from the bottom of the boat is being diverted into the water. Reflection is possible, causing superior mirages occasionally, but that light is thrown over the observer at the shore.  This is all slightly tricky, so please let me know if I can clarify anything for you.

Quote
And why does horizon distance increase with height?

Because of the typical air density gradient (you are looking through a less dense/less interacting media), and the angular resolution limits of the eye caused by the receptor density, lens shape, and processing limitations of the eye/camera.  If there were 100 clones lined up perfectly in front of you (and cannot move but up and down), you might see only the first until you are lifted up higher. We can't see through/behind stuff is roughly the simple answer.

Good questions, though I have to assume you were merely interested in my perspective on it - as these are 101 flat earth questions and you don't seem to be new!
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Tumeni on September 27, 2020, 01:14:18 PM
The horizon is an optical illusion, the "edge" of nothing but our vision, and we were all egregiously mistaught about it.

... but I/we can see things BEYOND the horizon. How could we do that, if it's at the limit of our vision?
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on September 27, 2020, 01:15:55 PM
... but I/we can see things BEYOND the horizon. How could we do that, if it's at the limit of our vision?
You can see through the Earth? That's impressive. Have you considered monetising this ability?
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Iceman on September 27, 2020, 02:09:53 PM
Many photographers have done just that - any time they sell a print of those city skyline pictures from across lakes on certain days. Making money off pictures of things beyond the horizon.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on September 27, 2020, 03:20:39 PM
Many photographers have done just that - any time they sell a print of those city skyline pictures from across lakes on certain days. Making money off pictures of things beyond the horizon.
In order to be "beyond" the horizon, they'd have to be on the same plane (or sphere) as the horizon. What you're talking about it objects which are above the horizon.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: AllAroundTheWorld on September 27, 2020, 04:21:17 PM
Many photographers have done just that - any time they sell a print of those city skyline pictures from across lakes on certain days. Making money off pictures of things beyond the horizon.
In order to be "beyond" the horizon, they'd have to be on the same plane (or sphere) as the horizon. What you're talking about it objects which are above the horizon.

Come on, dude.
You are playing silly semantic games here.
The original claim was that the horizon is the “edge of nothing but our vision”.
The implication is that we see a horizon because we can’t see any further.
If that were so then we wouldn’t be able to see anything beyond the horizon line. Here the word “beyond” clearly means “further away than”. I’m sure you understand that so why are you trying to wilfully misunderstand it to derail the discussion?
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on September 27, 2020, 05:06:38 PM
The original claim was that the horizon is the “edge of nothing but our vision”.
The implication is that we see a horizon because we can’t see any further.
This is accurate.

Here the word “beyond” clearly means “further away than”.
This is not.

If you choose to misrepresent the guy's argument, his argument sure is going to souind silly; but do you think you'll have much luck convincing him of your views if you open your argument with such an obvious strawman?
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Tumeni on September 27, 2020, 05:20:05 PM
What you're talking about it objects which are above the horizon.

No, that's not what is being talked about.

Beyond the horizon and still visible is both above the horizon and beyond it. Simple geometry.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on September 27, 2020, 05:21:50 PM
No, that's not what is being talked about.
I'm glad you agree - I was worried AATW may be correct, but now we know we no longer need to concern ourselves with objects above the horizon.

In that case, please detail your x-ray vision to us. I really think we may be on to something here - Tumeni, the man known for his honest assessment of the situation, is now claiming to be able to see through the surface of the Earth! Think about the military applications!
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Tumeni on September 27, 2020, 05:36:03 PM
No, that's not what is being talked about.
I'm glad you agree - I was worried AATW may be correct, but now we know we no longer need to concern ourselves with objects above the horizon.

In that case, please detail your x-ray vision to us. I really think we may be on to something here - Tumeni, the man known for his honest assessment of the situation, is now claiming to be able to see through the surface of the Earth! Think about the military applications!

(https://i.imgur.com/xYMNMK2.jpg)

Everything the observer can see above the orange line is above the horizon from the observer's view point. This could include objects nearer than the physical horizon point, at that distance, or farther away.

Objects can be seen above this line which are physically further from the observer than the physical horizon point, and they are beyond the horizon.

Nothing to do with seeing through the Earth.

No?

This can include airborne objects, shipping, and tall buildings as well as celestial bodies like the Moon.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on September 27, 2020, 06:12:28 PM
No?
No.

Every point of the moon you will actually be able to see in this scenario will be located, at least by a miniscule amount, above the horizon. You agreed that these aren't objects we're discussing.

What you're talking about it objects which are above the horizon.
No, that's not what is being talked about.

So, please get back to demonstrating your x-ray vision to us.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: AllAroundTheWorld on September 27, 2020, 09:44:12 PM
Here the word “beyond” clearly means “further away than”.
This is not.

Well, it is. It's the way I'm using the word.

Quote
If you choose to misrepresent the guy's argument, his argument sure is going to souind silly; but do you think you'll have much luck convincing him of your views if you open your argument with such an obvious strawman?

I'm not deliberately misrepresenting his argument, I'm starting to think I don't understand it.
I've had a go at showing what I'm trying to say but I am pretty awful at drawing diagrams.

(https://i.ibb.co/B2kZMd5/horizon.jpg)

So you have a tall building on the right and two viewing points on the left. In the RE model the horizon is simply the edge of the earth. It's nothing to do with how far you can see although if the horizon is far enough away then that may become a factor and the horizon would not be a sharp line as it usually is at low altitudes.

So if you're at the viewing position on the right at a certain viewer height then the red line is drawn so it touches the earth - that's the horizon. Everything below that line beyond the horizon is occluded by the earth, hence the bottom of the building not being visible. Everything above that line is visible because you have clear line of sight to it.

If you're further away the the left viewing position and the same viewer height then the horizon will be the same distance from you - blue line - but because you're further away, and thus further round the globe, you can see less of the distant building.

The Turning Torso video demonstrates all this quite nicely. Obviously this is all massively out of scale, in real life you're only talking about 1 or 2 degrees in most cases round the earth so the leaning away of the building would not be noticeable.

If you're at the left viewing position but at a higher viewer height - green line - then the horizon is further away and you can see more of the building.

If the horizon was simply the "edge of nothing but our vision", then why would you see any of the building which is further away than the horizon? And this is where I fear I've not understood his argument. Maybe you or he could draw something to demonstrate.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Tumeni on September 28, 2020, 05:11:37 AM
Every point of the moon you will actually be able to see in this scenario will be located, at least by a miniscule amount, above the horizon. You agreed that these aren't objects we're discussing.

... and the Moon is physically beyond the horizon, being further away than it. Depending on its position, part or all of it, from the observer's viewpoint, will be above the horizon, but it will not physically be at the same distance as the horizon.

So you agree that the observer can see things beyond the horizon, and that the horizon is not at a limit of vision.

No?
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on September 28, 2020, 05:18:11 AM
... and the Moon is physically beyond the horizon, being further away than it.
You agreed that objects located above the horizon are "not what is being talked about (https://forum.tfes.org/index.php?topic=16910.msg221673#msg221673)". Have you changed your mind?

No?
No.

You have yet to demonstrate that you can see beyond the horizon, rather than being able to see farther in directions that don't lead towards the horizon, or under conditions different than looking at the horizon.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Tumeni on September 28, 2020, 07:06:13 AM
... and the Moon is physically beyond the horizon, being further away than it.
You agreed that objects located above the horizon are "not what is being talked about (https://forum.tfes.org/index.php?topic=16910.msg221673#msg221673)". Have you changed your mind?

OK, let's review;

At #6, I said, in response to jack;

The horizon is an optical illusion, the "edge" of nothing but our vision, and we were all egregiously mistaught about it.

... but I/we can see things BEYOND the horizon. How could we do that, if it's at the limit of our vision?

to which you replied;

... but I/we can see things BEYOND the horizon. How could we do that, if it's at the limit of our vision?
You can see through the Earth? That's impressive. Have you considered monetising this ability?

...and you then replied to iceman with

Many photographers have done just that - any time they sell a print of those city skyline pictures from across lakes on certain days. Making money off pictures of things beyond the horizon.
In order to be "beyond" the horizon, they'd have to be on the same plane (or sphere) as the horizon. What you're talking about it objects which are above the horizon.

At which point, you seemed to be referring to something being physically above the horizon, at the same distance as the horizon.

AATW pointed out "You are playing silly semantic games here."
You then disagreed that "beyond" means "further away than"...

My #12 was written on the basis of you referring to "above the horizon" as being at the same distance as the horizon.

So .... from there on, I drew a diagram to show the physical placement of objects which could be beyond the horizon,
at a distance farther than the horizon, but explicitly stated that from the viewpoint of the observer, they
were simply "above" the horizon in line of sight.

I thought the diagram was clear, but ....

You have yet to demonstrate that you can see beyond the horizon, rather than being able to see farther in directions that don't lead towards the horizon, or under conditions different than looking at the horizon.

Semantics again.

Analogy; If you stand in the spectator area, looking along the centre, lengthwise, of a football pitch, you can see the goalposts at the near end, and those at the far end. If you look at those at the near end, you can also have the far posts in your field of vision. If you look at the far posts, then  yes, you looking in "directions that don't lead to the near posts, or under conditions different than looking at the near posts", but you are still looking at a set of posts which are beyond the near ones, which are still in your field of view.

Look out at the horizon. You can look AT the horizon, whilst also seeing objects in your field of view above it, which are beyond it, and also at the lands and sea which are in your field of view below it, and which are nearer than it. See diagram above. If the diagram is unclear, then, as AATW says, perhaps you could draw something to show what you mean?
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on September 28, 2020, 12:15:02 PM
OK, let's review;
Let's not. You said nothing that AATW hasn't already said, and I'm not a fan of wasting time. Please either back up or retract your claim that you posess X-ray vision.

Semantics again.
Not at all. I was pretty sure this is what you meant (in which case it was irrelevant to the discussion at hand, but at least it made some parsable sense), until the moment you explicitly stated that "this is not what is being talked about". I can't resolve this contradiction for you - you're gonna have to make up your mind. Either you are talking about things you can see above the horizon, or "this is not what is being talked about". Please choose.

Though I must say I find it funny that you take an issue with people expecting that your writing has meaning (semantics).

Once again:
If you choose to misrepresent the guy's argument, his argument sure is going to souind silly; but do you think you'll have much luck convincing him of your views if you open your argument with such an obvious strawman?
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: AllAroundTheWorld on September 28, 2020, 12:23:05 PM
I no longer think I understand his argument. I have provided a diagram with the RE explanation of horizon and seeing distant buildings or part of them.
If his argument is about limits of vision then I don't understand how you can see the distant building at all.
As I said, a diagram to explain what he thinks is going on would help.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on September 28, 2020, 12:59:53 PM
I don't want to make his argument for him (it's highly likely that we wouldn't agree on the specifics, so I have to leave that part to him), but it is crucial to keep in mind that visibility depends on a plethora of conditions.

Regardless of the actual reason for the horizon being as far as we can see (EA, perspective, atmospheric retraction, the Earth being round), the distinction between the horizon and things that aren't the horizon is essential.

Think of it that way: if you wanted to argue that the sinking ship effect proves that the Earth is round and I snapped back with "a-ha, but I can still see the mast, ergo I can see the boat, ergo it's not hidden at all!" you'd rightly lambast me for being insincere in my arguments. Tumeni is doing precisely that.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Tumeni on September 28, 2020, 01:35:00 PM
Please either back up or retract your claim that you possess X-ray vision.

I didn't claim that. You said that I did. Indulge us all, and tell us where you assert that I claimed it. Please.

Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on September 28, 2020, 01:42:15 PM
I didn't claim that.
But of course you did.

You were unclear at first:

... but I/we can see things BEYOND the horizon.

But when I suggested you're referring to objects located above the horizon, you helpfully clarified:

What you're talking about it objects which are above the horizon.
No, that's not what is being talked about.

So, we know that you claim to be able to see things BEYOND (sic) the horizon, and you are not talking about things above the horizon (or at least "it is not being talked about", in case there's a distinction).

Please substantiate or retract. I really hope you weren't trying to derail the thread with this nonsense.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Tumeni on September 28, 2020, 01:48:26 PM
Why are you still taking issue with reply #12, when I've posted #14, 17 and 19, all to expand on and clarify it, specifically in response to what you said in #13 and subsequent replies?
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Iceman on September 28, 2020, 01:51:01 PM
This thread has devolved to a painful level. If you watched a 'sinking ship' to the point where all you saw was the mast, regardless of your world view, you would know you were seeing something beyond the horizon - whatever 'horizon' means in your world view. The boat's hull has disappeared behind it, but the mast is still visible, but since we know the mast is part of that boat we watched disappear, the mast is clearly beyond what we perceive as the horizon.

In RE we argue that it is the curved surface of the water that is obstructing view of the bottom of the boat, in FE, its perspective, attack angle, angular resolution, EA, a fat morgana - whatever.

I'm not sure how we got to the point where we're arguing about the definition of 'beyond'
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on September 28, 2020, 02:23:50 PM
Why are you still taking issue with reply #12, when I've posted #14, 17 and 19, all to expand on and clarify it, specifically in response to what you said in #13 and subsequent replies?
Without spending too much time tracking down the random post numbers you're spewing out (you know how to use links and quotes): Because you keep contradicting yourself; and because your non-x-ray-vision argument is irrelevant to the thread.

So: are you wasting our time by claiming x-ray vision, or are you wasting our time with irrelevant remarks? Please make up your mind.

I'm not sure how we got to the point where we're arguing about the definition of 'beyond'
Well, any of you have the option of returning to arguing the original point instead of trying to redefine the word.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Tumeni on September 29, 2020, 05:38:12 PM
OK, I wrote three replies after the one you take issue with, clarifying what I took you and others to mean at that point, and clarifying what I meant. But you still focus on the reply before them, and seem to want to ignore the clarification. You've been asked to draw what you mean, but you've declined thus far.

I specified which replies they were, but you appear not to want to read them unless I link to them. You call them "random", but they are the actual reply numbers for those replies which I wrote. Not selected at random.

Beyond = physically farther away than.
Horizon = that physical point at which the land or sea appears to meet the sky
Above the horizon = 1. A physical point directly above that specified above, or
2. That which is in the observer's field of view nearer, above or beyond that physical point

Clear?
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on September 29, 2020, 07:19:27 PM
Clear?
No, by design on your part.

Look, Tumeni, this is simple. Option number 1 or option number 2? I only ask to find out whether you've completely lost it, or whether you deliberately tried to detail this thread.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Tumeni on September 30, 2020, 02:45:08 PM
Look, I've told you why I said what I said, I expanded on it and clarified it, telling everyone exactly which replies to look at to see such clarification.

You've indicated that you've deliberately not looked at my reply in one instance, and that you aren't willing to look at the others unless I link to them, even though the thread is barely two pages.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on September 30, 2020, 04:35:00 PM
Look, I've told you why I said what I said, I expanded on it and clarified it, telling everyone exactly which replies to look at to see such clarification.
Okay, if you don't wish to explain which of the two ways of wasting our time you're engaging in, then I'll just politely ask that you stop doing either.

If you're claiming to have x-ray vision, do so in CN. If you're derailing the thread with obvious strawman arguments, ideally don't do it anywhere.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Tumeni on September 30, 2020, 04:59:41 PM
Look, I've told you why I said what I said, I expanded on it and clarified it, telling everyone exactly which replies to look at to see such clarification.
Okay, if you don't wish to explain which of the two ways of wasting our time you're engaging in, then I'll just politely ask that you stop doing either.

If you're claiming to have x-ray vision, do so in CN. If you're derailing the thread with obvious strawman arguments, ideally don't do it anywhere.

Half of my replies are simply responding to you, and stating what I've said previously and why.

If you weren't so adamant that I claimed something that I didn't even mention ...
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Iceman on September 30, 2020, 05:00:23 PM
But Pete, you're the one who made the claim that the only way to see anything beyond the horizon is to see through the earth. A claim that is completely untrue given the examples listed above and the diagrams that accompanied them.

Everything in this thread after reply #6, when that re-framed the discussion, has been a bit of a trainwreck :s
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: AllAroundTheWorld on October 01, 2020, 08:40:08 AM
Maybe this helps if we're going to play semantic games

(https://i.ibb.co/71wLD1b/Above-And-Beyond.jpg)

I would say "on", rather than "above", but whatever.

And you could apparently see curvature from Concorde if you had a decent viewing angle, which had a cruising altitude of 60,000 feet, dragging this back kicking and screaming to the OP.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on October 01, 2020, 09:59:05 AM
But Pete, you're the one who made the claim that the only way to see anything beyond the horizon is to see through the earth. A claim that is completely untrue
In the context of this discussion, there is only one meaning of "beyond" that makes sense, and it is not the meaning the RE crowd keeps trying to force into this conversation. You're falling for a classic Tumeni troll. He's due a vacation soon anyway, but we've gotta give him his last chance before that happens. Until then, please just don't feed him.

In the meantime: You're responding to a specific poster who made a pretty specific claim. Changing the meaning of his words on him is a no-go, even if you don't like the way he chose his words. It doesn't matter how many diagrams you draw to demonstrate that your choice of words is better - it's still not the meaning intended in this discussion. If you continue doubling down on redefining the term, we'll continue getting absolutely nowhere.

If someone tells you you can't see past the horizon, it's pretty obvious that he's not talking about the things that are farther away from you than the horizon that you can see. Could it have been worded better? Yes. Should you have any difficulty understanding what he actually said? No.

Everything in this thread after reply #6, when that re-framed the discussion, has been a bit of a trainwreck :s
I agree, this has been mismanaged. I tried engaging Tumeni in discussion when I should have slapped him with a large trout and kicked him down to AR. I should have known better and I'll own up to that.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: AllAroundTheWorld on October 01, 2020, 10:15:41 AM
If someone tells you you can't see past the horizon, it's pretty obvious that he's not talking about the things that are farther away from you than the horizon that you can see.
The original quote is

Quote
The horizon is an optical illusion, the "edge" of nothing but our vision

So yeah, that's exactly what I took it to mean. If the horizon is the edge of our vision then how can we see things which are further than it?
I'm happy to concede I'm not understanding him, but I have suggested a diagram would help and none has been provided.

(I also agree that much of this should be split into a separate thread about what the horizon actually is)
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on October 01, 2020, 10:21:23 AM
So yeah, that's exactly what I took it to mean. If the horizon is the edge of our vision then how can we see things which are further than it?
Well, it very much is an edge of our vision, regardless of the model you choose. Much like with any other edge that obstructs our vision, it creates a blind spot. It doesn't magically nullify our vision.

When you encounter a blind corner while driving your vehicle, it doesn't mean that you absolutely cannot see further than that corner. It just means that you can't see beyond it.

I'm happy to concede I'm not understanding him, but I have suggested a diagram would help and none has been provided.
You can't see purple.

(https://i.imgur.com/q2r869W.jpg)

That's literally all there is to that part of the claim.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: AllAroundTheWorld on October 01, 2020, 10:42:50 AM
That's the RE claim (actually you can't see anything below the red line, but let's not split hairs), I'm pretty sure he's FE though so in the context of a FE I'm not clear what he means.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on October 01, 2020, 10:50:05 AM
That's the RE claim
Well, yes, I drew it on a RE diagram to avoid further confusion.

And yes, it really was that simple and obvious. This is why I'm particularly grumpy with people who fell for Tumeni's diversion here (myself included).

(actually you can't see anything below the red line, but let's not split hairs)
Yes - hence my multiple references to anything "not above the horizon".

I'm pretty sure he's FE though so in the context of a FE I'm not clear what he means.
I don't want to speak for him regarding the reason (as stated before, I have a hunch his views differ from mine). In the EA model, the effect is identical - you could draw the Earth's surface as straight, and your line of sight as curved, but the semantics behind the diagrams would be identical.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: AllAroundTheWorld on October 01, 2020, 11:24:21 AM
I don't want to speak for him regarding the reason (as stated before, I have a hunch his views differ from mine). In the EA model, the effect is identical - you could draw the Earth's surface as straight, and your line of sight as curved, but the semantics behind the diagrams would be identical.
Right. Agreed. I suspect his diagram would be different but unless he provides one there's no point in pursuing it. So here's a question, if I may. In the Wiki page about zeteticism it says:

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Zeteticism differs from the usual scientific method in that using zeteticism one bases his conclusions on experimentation and observation rather than on an initial theory that is to be proved or disproved. A zetetic forms the question then immediately sets to work making observations and performing experiments to answer that question, rather than speculating on what the answer might be then testing that out. For example, in questioning the shape of the Earth the zetetic does not make a hypothesis suggesting that the Earth is round or flat and then proceed testing that hypothesis; he skips that step and devises an experiment that will determine the shape of the Earth, and bases his conclusion on the result of that experiment

https://wiki.tfes.org/Zeteticism

So what does an observation of a sinking ship tell you? The RE proponent would say "Aha! You see? That demonstrates the sea is curving away from us". But if EA gives you an identical result on a FE then...well now what? The observation doesn't actually tell you anything about the shape of the earth. So what can we conclude from that observation about the shape of the earth?
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on October 01, 2020, 11:54:11 AM
So what can we conclude from that observation about the shape of the earth?
For that observation alone, it would seem to me that the simplest explanation is that the Earth is round. My second choice would be that it's inconclusive, but that requires additional interpretation as you've done above.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Iceman on October 01, 2020, 12:42:21 PM
What specifically has Tumeni been wrong about here? I'm starting to see that the issue relates to the differences in what the horizon is perceived as in FE vs. RE, but it shouldn't affect what Tumeni has said.

The start of the whole 'beyond the horizon' talk came after jack stated that the horizon was just the point where we cant see things anymore (oversimplified paraphrase there)

The follow up replies asked what about things that we see that are further than [the RE] horizon.

The implication of Jack's statement is that the horizon, in a FE context, is essentially a 2D plane, where some combination of perspective, angular resolution, air density, EA - whatever.

This is why the examples of sinking ships and city skylines were introduced. If you can only see the upper third of a building, boat mast or other physical features, the RE view is that the lower portion is hidden by the curvature of the earth (the pink line in Pete's version of the diagram). But we still see the upper portion because its tall enough to not be hidden. This means were seeing something we would argue is demonstrably further away than the horizon, which is, for all intents and purposes, a 1-dimensional line on the earth's surface.

Since its viewed as evidence for seeing curvature at ~5 ft of elevation, it's in the right thread here, weve just gone off the rails discussing the wrong aspects of the claims that have been brought forward.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: Pete Svarrior on October 01, 2020, 01:05:38 PM
What specifically has Tumeni been wrong about here?
It's time to can that angle of discussion. Tumeni tried changing the meaning of the word "beyond" as used in this conversation. The meaning has been clarified again and again and again and again, both with written descriptions and diagrams. Restating it for the 20th time won't help.

It is eminently clear what was meant, despite Tumeni's efforts. It's time to move on.
Title: Re: How High Do You Have To Be To See The Curvature?
Post by: jack44556677 on October 02, 2020, 07:04:34 PM
Wow, I feel a bit like urkel.  Did I do that?

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... but I/we can see things BEYOND the horizon. How could we do that, if it's at the limit of our vision?

Having read this whole thread, I am still not certain if this is (as pete concludes) a troll or not.  It certainly did spawn a tremendous amount of much ado about nothing - however that happens naturally!  It is not unclear that I meant beyond the horizon AT the horizon, and yet - I still find this question valid - but perhaps I'm getting punkd :(

Anyhow, I already gave the answer - just the reverse of it.  The line of sight that I described when explaining why you see farther at altitude, is the same line of sight to the distant tall object (just in reverse)!  I will draw a diagram if you still require clarification.