[JSS]

You have not understood my argument if you think I am saying that.  I am saying a circular distortion on a lens will not distort a circle.  You showed an oval which is not a circle, of course that will distort.

You're supposed to be arguing that the star trails are truly circular and not elliptical or oval. You claimed that the images showing non-circular star trails could have been affected by a warped lens. You guys then promoted the work of a photographer artist who you say is centering his warped lens on the center of rotation.

Ok first, I am not 'you guys'.  Please pay attention to who is making what argument.  I didn't post any star pictures in this thread but ones I took myself.

I am saying that you can not use random images off the internet to prove or disprove stars move in circles or ellipses. You don't know how the picture was taken or how it may have been processed.  Your random internet images of elliptical stars are not reliable, and other random images of circular images are not reliable. Because you don't know enough about either.

You asked some questions about how lenses worked and I answered them.

Once more, the pictures I have taken, myself, with known lenses and properly centered show them to be circular.  The math to calculate their positions also uses circular translation, and the stars are always where they are predicted to be. Moving in circular patterns.

Trying to take a partial curve from a picture where you don't understand the lens geometry or what post processing was done and then extrapolating that curve has so much margin for error it's completely useless as proof of anything, especially when as you did, drew your circles off center.

I might as well be claiming buildings curve because I can find pictures showing that they do. Does the following image prove that building curve? Why then would you assume the sky is curved based on random pictures?

[Tom Bishop]

I am saying that you can not use random images off the internet to prove or disprove stars move in circles or ellipses. You don't know how the picture was taken or how it may have been processed.  Your random internet images of elliptical stars are not reliable, and other random images of circular images are not reliable. Because you don't know enough about either.

Incorrect. If there are references in the image, you can see if the lens is warped or not.

But glad to see that you gave up on proving circular star trails.

You asked some questions about how lenses worked and I answered them.

Once more, the pictures I have taken, myself, with known lenses and properly centered show them to be circular.  The math to calculate their positions also uses circular translation, and the stars are always where they are predicted to be. Moving in circular patterns.

Oh, so we can't trust random images but we have to trust a rando on the internet who posts here trying to prove that the earth is round. 

[Iceman]

But the picture wasnt the only evidence was it.... all the star tracking software and apps show circular paths

[Tom Bishop]

But the picture wasnt the only evidence was it.... all the star tracking software and apps show circular paths

Do they? I just see a sentence on the internet.

[stack]

But glad to see that you gave up on proving circular star trails.

Do you want to argue about how cameras/lens optics work or about actual star observations?

As JSS pointed out here:

If stars were moving in ovals instead of circles then it would be unable to find them. I've done this countless times and can assure you it works. Why would I lie about something anyone can verify for yourself? Thousands of people use these scopes every day. If that's too expensive, star finders on your cell phone are cheap, and free. Easy enough to verify that the stars are right where they should be. Moving in circles. Not ovals.

And as Iceman just referenced, it's not about random cool looking star trail images found on the web, it's about the actual observation of stars. All of the software and almanacs would have the incorrect position for these stars according to your thinking. Observationally and objectively, that is not the case. And that is the point here.

Observationally, you know, zetetically, this is correct:



Observationally, you know, zetetically, you are not correct:

[JSS]

I am saying that you can not use random images off the internet to prove or disprove stars move in circles or ellipses. You don't know how the picture was taken or how it may have been processed.  Your random internet images of elliptical stars are not reliable, and other random images of circular images are not reliable. Because you don't know enough about either.

Incorrect. If there are references in the image, you can see if the lens is warped or not.

No, you can not.  Did you forget the picture I posted showing the blinds?  There were straight lines there, and very obviously warped ones.  Unless you think my blinds actually look like that.

You can not prove star trails are curved using random images without knowing how they were taken and processed.  Just like my blinds image proved, straight in one part of the image does not mean straight in another. You need to understand how lenses work before you start making claims like that.

But glad to see that you gave up on proving circular star trails.

What part of my post did you misunderstand to get that conclusion? I even posted my own star trails as my own proof. Please read responses more carefully and understand them before replying.

You asked some questions about how lenses worked and I answered them.

Once more, the pictures I have taken, myself, with known lenses and properly centered show them to be circular.  The math to calculate their positions also uses circular translation, and the stars are always where they are predicted to be. Moving in circular patterns.

Oh, so we can't trust random images but we have to trust a rando on the internet who posts here trying to prove that the earth is round. 

Yes, because I know all the parameters. I haven't been saying we can't trust random images because people are all lying about them, I'm saying you can't trust them because you do not have all the information needed to make that judgment. I do have all that information.

You don't have to trust me.  You are perfectly capable of taking your own star trail pictures if you think everyone is part of The Conspiracy and out to fool you. Like I'd lie about something anyone can verify themselves. Not my problem to deal with your trust issues.

Feel free to try, just make sure to document what lens or telescope you use, the settings and any post-processing you do. Because apparently you can't trust a random internet weirdo.

[stack]

But the picture wasnt the only evidence was it.... all the star tracking software and apps show circular paths

Do they? I just see a sentence on the internet.

It's a claim. A claim is evidence, right?

[Tom Bishop]

I am saying that you can not use random images off the internet to prove or disprove stars move in circles or ellipses. You don't know how the picture was taken or how it may have been processed.  Your random internet images of elliptical stars are not reliable, and other random images of circular images are not reliable. Because you don't know enough about either.

Incorrect. If there are references in the image, you can see if the lens is warped or not.

No, you can not.  Did you forget the picture I posted showing the blinds?  There were straight lines there, and very obviously warped ones.  Unless you think my blinds actually look like that.

Yes, the straight lines of the blinds were warped. That's how we know that the lens was distorted. If there are references in the image, you can see if the lens is warped or not.

There were straight lines in other images posted and they were straight across various parts of the image, and not warped, showing that the lens was not distorted by a similar effect.

Like I'd lie about something anyone can verify themselves.

You've come here to lie before. You had previously claimed that you were a computer programmer who has programmed gravity simulations and knew that Numerical Solutions accurately simulated gravity. You lied to us - https://wiki.tfes.org/Numerical_Solutions

Now in this thread you're an astrophotographer claiming to have special knowledge.

[Tom Bishop]

But glad to see that you gave up on proving circular star trails.

Do you want to argue about how cameras/lens optics work or about actual star observations?

As JSS pointed out here:

If stars were moving in ovals instead of circles then it would be unable to find them. I've done this countless times and can assure you it works. Why would I lie about something anyone can verify for yourself? Thousands of people use these scopes every day. If that's too expensive, star finders on your cell phone are cheap, and free. Easy enough to verify that the stars are right where they should be. Moving in circles. Not ovals.

And as Iceman just referenced, it's not about random cool looking star trail images found on the web, it's about the actual observation of stars. All of the software and almanacs would have the incorrect position for these stars according to your thinking. Observationally and objectively, that is not the case. And that is the point here.

Observationally, you know, zetetically, this is correct:



Observationally, you know, zetetically, you are not correct:

Both the distances and angles between the stars change throughout the night in stellarium.

[JSS]

I am saying that you can not use random images off the internet to prove or disprove stars move in circles or ellipses. You don't know how the picture was taken or how it may have been processed.  Your random internet images of elliptical stars are not reliable, and other random images of circular images are not reliable. Because you don't know enough about either.

Incorrect. If there are references in the image, you can see if the lens is warped or not.

No, you can not.  Did you forget the picture I posted showing the blinds?  There were straight lines there, and very obviously warped ones.  Unless you think my blinds actually look like that.

Yes, the straight lines of the blinds were warped. That's how we know that the lens was distorted. If there are references in the image, you can see if the lens is warped or not.

There were straight lines in other images posted and they were straight across the image, and not warped, showing that the lens was not distorted by a similar effect.

My image had lines of the blinds that were NOT warped, there is your 'straight line reference' so how can you say those lines don't count but the lines in your pictures do?

Like I'd lie about something anyone can verify themselves.

You continuously come here to lie. You had previously claimed that you were a computer programmer who has programmed gravity simulations and knew that Numerical Solutions accurately simulated gravity. You lied to us - https://wiki.tfes.org/Numerical_Solutions

Now in this thread you're an astrophotographer pretending to have special knowledge.

You called me a liar down in AR but do you really want to do that again up here now? Can you prove I am not a programmer? Can you prove I haven't written n-body simulation software? Can you prove I don't take pictures of stars and planets which is what astrophotography is. I post pictures I take all the time, and I am pretty sure that yes, I have special knowledge about how those were taken, because I took them. How can you say with a straight face I'm only pretending to know how I take my own pictures? 

Posting a link to a wiki page you wrote is not proof I am lying.

I even offered to write an n-body simulator in any language you wanted to challenge your calling me a liar, but you backed down and abandoned the discussion.

Can we keep this civil and not resort to personal attacks?

[JSS]

Both the distances and angles between the stars change throughout the night in stellarium.

Incorrect.  You are showing a simulated extreme wide-angle lens with a 185 degree FOV.  This is obvious from the line of trees around the edge of the image you provided. 

The image is heavily distorted and warped, which should be clear to see at first glance, especially as it says in the upper right what the lens FOV is, which you cropped from your screenshots.  Below is the full screenshot with the FOV data included. 

If you want to do this test correctly you need to use a lens with less distortion like this.  In the second image you can see the distance is correct between the two times as the Earth rotates, showing that the software is indeed moving them in a perfect circle. Not an ellipse.

If you want more conformation of what the software is displaying, you can click on the stars in Stellarium and it gives you their exact position, which you can then use to calculate distances and see that they do not change. This is a far better method than taking screenshots of an obviously warped image and trying to measure pixels.

[Tom Bishop]

Can you prove I haven't written n-body simulation software?

Your personal claims of special knowledge don't mean much here. If you want to continue to claim that you're a computer programmer and have special knowledge about numerical solutions I can only encourage you to demonstrate it.

Both the distances and angles between the stars change throughout the night in stellarium.

Incorrect.  You are showing a simulated extreme wide-angle lens with a 185 degree FOV.  This is obvious from the line of trees around the edge of the image you provided. 

The image is heavily distorted and warped, which should be clear to see at first glance, especially as it says in the upper right what the lens FOV is, which you cropped from your screenshots.  Below is the full screenshot with the FOV data included. 

Astronomy programs like Stellarium produce a polar projection, and would be identical to where one was laying down and observing the sky with their ~180 degree field of view.

https://www.e-education.psu.edu/eme810/node/534

[stack]

Astronomy programs like Stellarium produce a polar projection, and would be identical to where one was laying down and observing the sky with their ~180 degree field of view.

Stellarium let's you select from 8 projections:

3.3 Projection
3.3.1 Perspective
3.3.2 Equal Area
3.3.3 Stereographic
3.3.4 Fish-eye
3.3.5 Hammer-Aitoff
3.3.6 Cylinder
3.3.7 Mercator
3.3.8 Orthographic

From your image, it looks like you selected maybe Orthographic. I believe the default is "Perspective" with a 60° FOV. Why did you pick something other than the default?

[JSS]

Can you prove I haven't written n-body simulation software?

Your personal claims of special knowledge don't mean much here. If you want to continue to claim that you're a computer programmer and have special knowledge about numerical solutions I can only encourage you to demonstrate it.

Tom, I offered to demonstrate it a long while back, remember how I offered to write an n-body simulation in any language you wished?  I've also written a computer program and posted it here recently, you should remember that as Pete took great pleasure in making fun of my 5 minutes of crappy effort.

You abandoned that discussion and never took me up on the offer, so you look pretty silly suddenly demanding I do so now. 

When did I claim I have 'special knowledge' of numerical simulations?  By saying I can write them?  They are very simple to do, any first year comp-sci major could write one, and easily wrine an n-body simulatort as well. It's not hard to do at all.

Both the distances and angles between the stars change throughout the night in stellarium.

Incorrect.  You are showing a simulated extreme wide-angle lens with a 185 degree FOV.  This is obvious from the line of trees around the edge of the image you provided. 

The image is heavily distorted and warped, which should be clear to see at first glance, especially as it says in the upper right what the lens FOV is, which you cropped from your screenshots.  Below is the full screenshot with the FOV data included. 

Astronomy programs like Stellarium produce a polar projection, and would be identical to where one was laying down and observing the sky with their ~180 degree field of view.

Did you not understand my post?  I showed you that the FOV in your examples is 185 degrees which is extremely distorted, mine at 16 degrees is not.

You do not seem to understand how projections work, you are tying to measure lines on a polar projection on a flat surface to get distances, and of course that isn't going to work.

You can not just measure lines randomly on polar projections, you get nonsense results as you did.

[Tom Bishop]

Did you not understand my post?  I showed you that the FOV in your examples is 185 degrees which is extremely distorted, mine at 16 degrees is not.

Field of View has nothing to do with distortion. Human vision has a FOV of about 190 degrees.

"our eyes sit in the front of our head, allowing us to see about 60 percent of world in front of us with both eyes, at the compromise that we can only see at maximum about 190 degrees around us (Block 1969; Wolfe 2006)" – Human Spatial Navigation, 2018, p.73

Tom, I offered to demonstrate it a long while back, remember how I offered to write an n-body simulation in any language you wished?  I've also written a computer program and posted it here recently, you should remember that as Pete took great pleasure in making fun of my 5 minutes of crappy effort.

You abandoned that discussion and never took me up on the offer, so you look pretty silly suddenly demanding I do so now.

When did I claim I have 'special knowledge' of numerical simulations?  By saying I can write them?  They are very simple to do, any first year comp-sci major could write one, and easily wrine an n-body simulatort as well. It's not hard to do at all.

Since we have contemporary sources saying that you are incorrect about Numerical Simulations, you're incorrect.

If you are going to argue something, you need to demonstrate it, not claim that you have special knowledge and have special credentials.

[stack]

Did you not understand my post?  I showed you that the FOV in your examples is 185 degrees which is extremely distorted, mine at 16 degrees is not.

Field of View has nothing to do with distortion. Human vision has a FOV of about 190 degrees.

When combined with an almost fisheye perspective like you applied it sure does have something to do with it. Is this how humans see with the land wrapped around us like a cylinder:

[Tom Bishop]

When combined with an almost fisheye perspective like you applied it sure does have something to do with it. Is this how humans see with the land wrapped around us like a cylinder

If you lay down in a field or cleared out area and look up at the sky you do see land and land features 360 degrees around your vision.

[stack]

When combined with an almost fisheye perspective like you applied it sure does have something to do with it. Is this how humans see with the land wrapped around us like a cylinder

If you lay down in a field or cleared out area and look up at the sky you do see land and land features 360 degrees around your vision.

No you wouldn't.

[Tom Bishop]

When combined with an almost fisheye perspective like you applied it sure does have something to do with it. Is this how humans see with the land wrapped around us like a cylinder

If you lay down in a field or cleared out area and look up at the sky you do see land and land features 360 degrees around your vision.

No you wouldn't.

Actually, you would.

http://www.vision-and-eye-health.com/visual-field.html

[stack]

When combined with an almost fisheye perspective like you applied it sure does have something to do with it. Is this how humans see with the land wrapped around us like a cylinder

If you lay down in a field or cleared out area and look up at the sky you do see land and land features 360 degrees around your vision.

No you wouldn't.

Lie down on the ground. Can you see your feet? Can you see the surface beyond your feet? Can you see the ground surface off the top of your head? Side to side, can you see the ground surface to your left and to your right when looking straight up?