I'm taking another try at this-how to process 26 image DNG pano

[Robert Prior]

Use Winrar and you will have no problem.

On a Mac, so that's not an option. :-(

 

[Jagerbomb52]

On a Mac, so that's not an option. :-(

Well sorry but I am not uploading 669 MB again LOL

 

[Robert Prior]

Thanks to everyone who answered or tried to answer my questions. This post got kind of hi-jacked from the OP so if I have any other questions I will for sure start my on post. After all the solutions I have decided to just use PanoramaStudio 3 Pro as it loads DNG files just fine and outputs them as TIFF file for later editing in Photoshop or Lightroom.
In case anyone is interested in the final photo you can find it here.

New panorama3 with photoshop adjustments

New panorama3 with photoshop adjustments

kuula.co

Cool pano!

 

[Robert Prior]

Well sorry but I am not uploading 669 MB again LOL

No worries. You got it working and that's the important thing.

 

[sar104]

I believe you’re seeing a player artifact, not a problem with the stitch.

Any flat view of a spherical pano wider than about 110-deg can look like that. If you zoom in a little on Meta4’s Kuula image it straightens out.

I don't think that's the explanation. In fact I know it isn't. It's a projection issue. If you take a set of approximately linear images representing a non-planar view (4π) and stitch them to a planar projection then the resulting image is geometrically distorted, and that distortion is not corrected by putting them back into a spherical projection. They need to be projected spherically in the pano process.

 

[SethB]

I don't think that's the explanation. In fact I know it isn't. It's a projection issue. If you take a set of approximately linear images representing a non-planar view (4π) and stitch them to a planar projection then the resulting image is geometrically distorted, and that distortion is not corrected by putting them back into a spherical projection. They need to be projected spherically in the pano process.

If I’m following your post, you’re saying the pano was perhaps created as a cylindrical projection? even orthographic?

I’m not that familiar with kuula.com, the players I’ve used will reject an image that doesn’t have the 2:1 aspect ratio of a proper equirectangular pano.

This is a pretty good reference for different projections (link).

 

[sar104]

If I’m following your post, you’re saying the pano was perhaps created as a cylindrical projection? even orthographic?

I’m not that familiar with kuula.com, the players I’ve used will reject an image that doesn’t have the 2:1 aspect ratio of a proper equirectangular pano.

This is a pretty good reference for different projections (link).

A basic pano is obviously a flat projection in which a complete or partial sphere is projected onto a plane image format. It's definitely not orthographic. Remapping such a pano to the original, undistorted spherical view (the navigable panos in question here) doesn't have a general solution without a detailed description of the original projection method and field of view. That's why, if the goal is a navigable spherical pano, it's far better to project the individual original images that comprise it directly onto a spherical surface rather than going via a plane projection.

You may well be right that some "players" only take a plane pano as input rather than the original 4π base images, but that's never going to work as well as going direct.

 

[SethB]

…That's why, if the goal is a navigable spherical pano, it's far better to project the individual original images that comprise it directly onto a spherical surface rather than going via a plane projection.

You may well be right that some "players" only take a plane pano as input rather than the original 4π base images, but that's never going to work as well as going direct.

Is there an accessible method to do this, such as a web hosting service? I‘m a little confused as to whether you’re talking theory or practice.

My understanding is that most (all?) of the current projection & display methods are based on the work of Helmut Dersch. If I recall, Dr. Dersch created a method based on unwrapping the sphere into an equirectangular projection that could be saved as a jpg or whatever, then rewrapping it to spherical for flat displays to show a section of it. Having worked in panoramic stills and video for many years, I can share that any flat display I’ve seen is a fairly poor representation of the sphere. A VR headset does *so* much better at this, offering an immersive experience. Flat displays don’t, and won’t.

Dr. Dersch created a series of command-line utilities called Panorama Tools, which were the basis for the GUIs in the shareware/open source Hugin and the commercial product PTGui (PanoTools GUI).

 

[sar104]

Is there an accessible method to do this, such as a web hosting service? I‘m a little confused as to whether you’re talking theory or practice.

My understanding is that most (all?) of the current projection & display methods are based on the work of Helmut Dersch. If I recall, Dr. Dersch created a method based on unwrapping the sphere into an equirectangular projection that could be saved as a jpg or whatever, then rewrapping it to spherical for flat displays to show a section of it. Having worked in panoramic stills and video for many years, I can share that any flat display I’ve seen is a fairly poor representation of the sphere. A VR headset does *so* much better at this, offering an immersive experience. Flat displays don’t, and won’t.

Dr. Dersch created a series of command-line utilities called Panorama Tools, which were the basis for the GUIs in the shareware/open source Hugin and the commercial product PTGui (PanoTools GUI).

I was broadly speaking theoretically, but PTGui appears to map the individual images onto a spherical surface, with minimal distortion, so that was my reference example of such a method in practice.

Your key point is the concept of projecting (unwrapping) a sphere into a flat JPEG that can still be used to recreate a distortion-free spherical projection for viewing. That was what @Meta4 was referring to, but the examples in this thread show variable geometric distortion on panning, so it's not working correctly, at least in those cases.

The use of a flat display to show a particular section of the spherical view is just equivalent to projecting the image that would have been recorded in that direction originally. The wider the field of view projected the more geometric distortion occurs - just like in a single photograph.