On a globe model the sea 'level' curves away (drops) from the viewer at 8 inches per mile squared , the horizon is 3 to 4 miles away .So the horizon can't be eye-level, that's impossible.8×(4×4) gives 128 inch drop.The horizon will always be far lower than the viwer.
Your channel does a great job of demonstrating evidence for curvature, and I thank you for your efforts. On this setup, I think there may be one potential source for inaccuracy- if the viewing tube and the level are not strictly parallel in 3d space, it may be that "level" for the level puts the viewing tube at some non-level angle. Imagine setting a chopstick on a table, then place another chopstick on top so it forms an X. One end of the 2nd chopstick may touch the table while the other sticks up in the air, right? You could end up with a similar relative tilt based on slack in the tape with your current setup. To reduce errors, perhaps you could attach a u-shaped flexible tube to each end of the viewing tube, and fill it with water. As long as there are no trapped bubbles in the line and not too much wind blowing over the top (which would cause pressure differences due to venturi effect), this can give you a very long baseline level which is easier to guarantee matches the orientation of the viewing tube.
Thanks! I actually did this observation years ago and I was in a hurry, but yeah all of your suggestions are good and I'm planning to do it better one of these days! However, my glass tube and aluminum tube were parallel to within probably a hundredth of a degree or better (I could tell by sighting from the top and see that they were parallel.) And since it was also right to left level, that too would diminish the effect. I have also used the water tube level: czcams.com/video/zwdwz8O3qg4/video.html I thought about connecting the tops of the water tube with an air line so that air could pass back and forth (i.e. it would form a large loop) but wind could not get in.
At that range, being off even 0.3 degrees by the time you reach the far shore will change where level appears in the tube: anywhere in the tube FOV could be level. Photographing laser from perpendicular, with many miles of beam in-frame, nullifies the need of knowing exact-level, the beam reaching target is sufficient, and a optical system capable of detecting changes of 0.1 degree, or less, in direction.
> _At that range, being off even 0.3 degrees_ Agreed, but my tube wasn't off by 0.3 degrees. It was within arcseconds. That level was incredibly sensitive, more sensitive than the bubble levels on a theodolite and those level to within a few arcseconds with a bubble level about 1/20th as long! > _Photographing laser from perpendicular, with many miles of beam in-frame, nullifies the need of knowing exact-level, the beam reaching target is sufficient,_ Not exactly. We know, without any doubt, that air changes density with temperature, and that temperature gradients readily form above the surface of water and ice, and that density gradients can and do cause light to follow a non-straight path. Without knowing the air density gradient along the path, it is not sufficient to just have the beam reach the target. Knowing the exact level is just one more way to verify that you're seeing what you think you're seeing. For example, your laser beam may reach the target. But what if your target is BELOW you, but you have to point the laser beam at a slight UPWARD slope? Then you know that the light is in fact curving downward, and that simply hitting your target is no longer sufficient. > _and a optical system capable of detecting changes of 0.1 degree, or less, in direction._ It is good to have a system that can detect small changes of angle. That's why I like theodolites, they can detect a change of 0.0003 degrees of change (1 arcsecond.) For example, check this video - I have the camera physically BELOW that metal sign. And yet I can see the waterline of the ship. There is no doubt that I could hit the waterline on the ship with a laser. And yet, the sign is physically higher than both the observer and the target. So just reaching the target is not sufficient. czcams.com/video/sMTQgsSbioc/video.html Because I had to point the theodolite ABOVE eye-level to center it on something that I KNOW is BELOW eye-level, I therefore know that the light was curving downward. And I think we both agree that downward curving light could allow us to see over a curved earth.
@@fromjesse Jesse, you totally missed why level is unnecessary. You cannot use a theodolite to measure the laser from perpendicular, for the same cause of the inaccuracy of your water level. That water level is not a quarter mile equivalent, even were it equivalent, it's like leveling a 20ft board with a torpedo-level. I believe the more light curves, the less probable a coherent projection.
With some extra devising and splicing, using a theodolite for measuring the perpendicular may well be plausibe, though much uglier and more complicated for teaching purposes.
@@speakingthetruthinallthere1005 I'm not sure I'm understanding what you're saying. But my best theodolite is rated at having an error of plus or minus 0.5 arcseconds, which is 1mm at 1/4 mile. So if I know the air density gradient along the path, why couldn't I measure the laser from perpendicular?
No, I had it leveled _with_ the weight of the camera, and when I removed the camera, the reduced weight caused that end to go up. The bubble was EXTREMELY sensitive, it moved drastically for mere arcseconds.
So not curved then. Well done Jesse. Notice how when you zoomed out it gave the appearance that the FOV of the mountain in the tube had sunk compared to the outer rim of the tube compared to when zoomed in it was sitting level? This is the parallax thanks to the angular size change.
@@fromjesse I left you a community post showing visually what is meant. You might want to realise everything you present is based on the earth been a flat plane with topography :)
@@FlatzoidsPerspective Well I guess it doesn't really matter if it's flat, so long as it measures as curved :D Thanks for the diagram, but you don't have the horizontal line position correctly. Not that I blame you, a simple chunk of pipe is not the greatest sighting device LOL but I used it by request. Ultimately though, the building, which is180 feet taller than the observer still appeared below eye-level, even when sighted using a leveled pipe. This matches globe earth perfectly, and has no TESTABLE explanation on a flat earth. Why can't I build a 1/100th scale model and get the exact same effect for the exact same reason?
On a globe model the sea 'level' curves away (drops) from the viewer at 8 inches per mile squared , the horizon is 3 to 4 miles away .So the horizon can't be eye-level, that's impossible.8×(4×4) gives 128 inch drop.The horizon will always be far lower than the viwer.
As first impression this prove curvature.
Nice demonstration!
Yet more evidence that we live on a globe slowly rotating at 15 degrees per hour.
Plus 360 degrees per year.
@@ReinoGoo Yes indeed.
Well it just so happens that is the exact speed the sun moves across the sky...coincidence?
@@MATT-qu7pl Pure coincidence.
@@MATT-qu7pl Must be 🤣
Your channel does a great job of demonstrating evidence for curvature, and I thank you for your efforts.
On this setup, I think there may be one potential source for inaccuracy- if the viewing tube and the level are not strictly parallel in 3d space, it may be that "level" for the level puts the viewing tube at some non-level angle. Imagine setting a chopstick on a table, then place another chopstick on top so it forms an X. One end of the 2nd chopstick may touch the table while the other sticks up in the air, right? You could end up with a similar relative tilt based on slack in the tape with your current setup.
To reduce errors, perhaps you could attach a u-shaped flexible tube to each end of the viewing tube, and fill it with water. As long as there are no trapped bubbles in the line and not too much wind blowing over the top (which would cause pressure differences due to venturi effect), this can give you a very long baseline level which is easier to guarantee matches the orientation of the viewing tube.
Thanks! I actually did this observation years ago and I was in a hurry, but yeah all of your suggestions are good and I'm planning to do it better one of these days! However, my glass tube and aluminum tube were parallel to within probably a hundredth of a degree or better (I could tell by sighting from the top and see that they were parallel.)
And since it was also right to left level, that too would diminish the effect. I have also used the water tube level: czcams.com/video/zwdwz8O3qg4/video.html
I thought about connecting the tops of the water tube with an air line so that air could pass back and forth (i.e. it would form a large loop) but wind could not get in.
At that range, being off even 0.3 degrees by the time you reach the far shore will change where level appears in the tube: anywhere in the tube FOV could be level.
Photographing laser from perpendicular, with many miles of beam in-frame, nullifies the need of knowing exact-level, the beam reaching target is sufficient, and a optical system capable of detecting changes of 0.1 degree, or less, in direction.
> _At that range, being off even 0.3 degrees_
Agreed, but my tube wasn't off by 0.3 degrees. It was within arcseconds. That level was incredibly sensitive, more sensitive than the bubble levels on a theodolite and those level to within a few arcseconds with a bubble level about 1/20th as long!
> _Photographing laser from perpendicular, with many miles of beam in-frame, nullifies the need of knowing exact-level, the beam reaching target is sufficient,_
Not exactly. We know, without any doubt, that air changes density with temperature, and that temperature gradients readily form above the surface of water and ice, and that density gradients can and do cause light to follow a non-straight path. Without knowing the air density gradient along the path, it is not sufficient to just have the beam reach the target.
Knowing the exact level is just one more way to verify that you're seeing what you think you're seeing.
For example, your laser beam may reach the target. But what if your target is BELOW you, but you have to point the laser beam at a slight UPWARD slope? Then you know that the light is in fact curving downward, and that simply hitting your target is no longer sufficient.
> _and a optical system capable of detecting changes of 0.1 degree, or less, in direction._
It is good to have a system that can detect small changes of angle. That's why I like theodolites, they can detect a change of 0.0003 degrees of change (1 arcsecond.)
For example, check this video - I have the camera physically BELOW that metal sign. And yet I can see the waterline of the ship. There is no doubt that I could hit the waterline on the ship with a laser. And yet, the sign is physically higher than both the observer and the target. So just reaching the target is not sufficient. czcams.com/video/sMTQgsSbioc/video.html
Because I had to point the theodolite ABOVE eye-level to center it on something that I KNOW is BELOW eye-level, I therefore know that the light was curving downward.
And I think we both agree that downward curving light could allow us to see over a curved earth.
@@fromjesse Jesse, you totally missed why level is unnecessary. You cannot use a theodolite to measure the laser from perpendicular, for the same cause of the inaccuracy of your water level. That water level is not a quarter mile equivalent, even were it equivalent, it's like leveling a 20ft board with a torpedo-level.
I believe the more light curves, the less probable a coherent projection.
With some extra devising and splicing, using a theodolite for measuring the perpendicular may well be plausibe, though much uglier and more complicated for teaching purposes.
@@speakingthetruthinallthere1005 I'm not sure I'm understanding what you're saying. But my best theodolite is rated at having an error of plus or minus 0.5 arcseconds, which is 1mm at 1/4 mile.
So if I know the air density gradient along the path, why couldn't I measure the laser from perpendicular?
@@speakingthetruthinallthere1005 I'm not sure what it is that you're trying to say here. Could you elaborate perchance?
It looks curved, but we know it's flat because we trust our senses.
Yes, we have to trust Dave Weiss's senses!
Our vision is a NASA shill.
What was the atmosphere doing at the time of observation? First few hundred feet of altitude....
What would you do with that information? Giving it to you would be like explaining to a possum that it should avoid traffic 🙄
So you rested some weight of the camera on observation end and it made that end go up????
No, I had it leveled _with_ the weight of the camera, and when I removed the camera, the reduced weight caused that end to go up.
The bubble was EXTREMELY sensitive, it moved drastically for mere arcseconds.
Thickest dimwit on CZcams says what?
And this means what, exactly?
Curven Erfen :D
Honestly? Horizon rising to eye level destroyed
It debunked the ludicrous space pizza world claim. Perhaps press play next time?
@@fromjesse
How is that exactly? You have a target in your tube. That’s it. Where is the curve?
As you said, it’s dicey. What’s that the fk mean?
Horizontal rising above eye level (when level is level instead of horizontal).
So not curved then. Well done Jesse.
Notice how when you zoomed out it gave the appearance that the FOV of the mountain in the tube had sunk compared to the outer rim of the tube compared to when zoomed in it was sitting level?
This is the parallax thanks to the angular size change.
What you say makes no sense.
The building top is 180ft higher than the observer, and should have been ABOVE the center of the tube end.
Goodbye imaginary pancake.
@@fromjesse I left you a community post showing visually what is meant. You might want to realise everything you present is based on the earth been a flat plane with topography :)
@@FlatzoidsPerspective Well I guess it doesn't really matter if it's flat, so long as it measures as curved :D
Thanks for the diagram, but you don't have the horizontal line position correctly. Not that I blame you, a simple chunk of pipe is not the greatest sighting device LOL but I used it by request.
Ultimately though, the building, which is180 feet taller than the observer still appeared below eye-level, even when sighted using a leveled pipe.
This matches globe earth perfectly, and has no TESTABLE explanation on a flat earth.
Why can't I build a 1/100th scale model and get the exact same effect for the exact same reason?
@@FlatzoidsPerspective
"the FOV of the mountain"
What is that supposed to mean?
Optical devices have a field of view, mountains don't.