# Soundly Proving the Curvature of the Earth at Lake Pontchartrain

I noticed that one or two people wondered if refraction was causing the curve of the towers to be exaggerated closer to the horizon. Well, I don't think so.

If you look at the picture, there are as many towers in the last 20% of the line as there are in the 80% closest to the observer. That's why the towers further out appear to curve more. The curve over the first 80% of the line is the same curve as the one represented by the last 20%, which is compressed into a quarter of the space.

Still don't understand 'no click'. Please delete.

Still don't understand 'no click'. Please delete.

I like fun little experiments and science demonstrations.

Here's a level (with a known straight edge), and on top of that there's a 1/8" steel bar, balanced on two spacers near the middle, meaning it curves down at the ends.

From a distance:

The straight edges are still perfectly straight, but the curves in the bar are much more apparent.

Now the other way, moving the supports so it sags in the middle:

"You can't make a curve out of a straight line with perspective."

You could not be more wrong. There are countless designs where CURVES, are made up of straight lines, and your perspective on those lines create the curve..

Last edited by a moderator:
You could not be more wrong. There are countless designs where CURVES, are made up of straight lines, and your perspective on those lines create the curve..
But here we are talking about a single straight line. Not multiple lines.

It’s impossible to make the straight edge on the red level look anything other than straight with perspective (unless you use a non-rectilinear lense) and certainly impossible to make it curve over and behind the horizon, regardless of lens.

You could not be more wrong. There are countless designs where CURVES, are made up of straight lines, and your perspective on those lines create the curve.

Could you provide one or two examples please?

But here we are talking about a single straight line. Not multiple lines.

It’s impossible to make the straight edge on the red level look anything other than straight with perspective (unless you use a non-rectilinear lense) and certainly impossible to make it curve over and behind the horizon, regardless of lens.

New member here. The use of these camera angles to compress what we are looking at into a smaller space to show existing warps or bends really works. It shows existing curves that would not otherwise be seen. I've seen this used for instance on runways, where you can clearly see how warped a runway is by looking at it from these compressed angles. Even to the point where you can see a plane landing gear disappear behind such curves or warps on the runway. It really works. Here is an example.

Source: https://youtu.be/7P9OAng32F0?t=55s

[Mod: Edits for clarity]

Last edited by a moderator:
Lake pontchartrain is a maximum of 16' deep, it would be impossible to have that much curvature on 16 feet of water the lake would be dry in the center.

When flat earthers question the authenticity of Soundly's photos based on distortion near the surface or fakery by Soundly, it may be useful to point out that distant mountains, buildings, and ships, drop down in elevation by the same amounts as Soundly's bridges at equal distances, even though the mountains are far above the distortion near the water surface. And flat earthers can likely verify this somewhere much closer to their home, though they may need to know trigonometry and have a theodolite or water level. Even if they come up with some other excuse to maintain their belief, it may be helpful if they can realize that Soundly's photos are not fakes or freaks, but show drops that are consistent with and readily verifiable in many other places.

Lake pontchartrain is a maximum of 16' deep, it would be impossible to have that much curvature on 16 feet of water the lake would be dry in the center.
This post illustrates a common misconception about curvature. Everything curves, including the datum (baseline) from which we measure heights and depths. The surface of the sea (of which Lake Pontchartrain is a part, despite the name) is at sea level, which is a curve, and the depth is measured relative to that.

Lake pontchartrain is a maximum of 16' deep, it would be impossible to have that much curvature on 16 feet of water the lake would be dry in the center.
Brilliant!