How to make orthogonal/multi-viewpoint panoramas in Photoshop?

[mikalj11434475]

I'm trying to create multipoint (aka orthogonal or linear) panoramas from multiple overlapping photos of artwork along a flat wall. Some times they come out reasonably well, but mostly they don't. I realize that most panorama programs assume photographs are taken by rotating around a fixed point, not moving in parallel to a plane.
My workflow, that someone else suggested online and the best I have so far, has been this:

Within Lightroom Develop module--> enable lens correction -->select photos—>right-click and select "edit in panorama in Photoshop." This brings up the dialog box in Photoshop with the files listed. I click to enable lens correction and click okay. It takes forever, the panorama stitches, but the output is disjointed and janky. I’ve tried all the panorama modes. Some are worse than others and none are good.

Exporting the sequence of shots as smaller .jpg files and then importing those into Photoshop speeds things up, but the stitching and alignment is still not even close.

The panoramas that work the best are the ones shot with the camera in landscape mode. Most sequences, the ones that don’t work at all, were shot in portrait mode. There is 30%-50% overlap, which should be more than enough. 

My first question is how to do this at all, since the workflow I’ve got isn’t working. 

Second question is, assuming this gets figured out, how large of a panorama can Photoshop handle? Some of these walls might be 50’ long by 8’ tall and I want them at very high resolution so that they can be zoomed in for details. That might be 50 or more original overlapping shots.

I have a few more questions, but they're somewhat irrelevant until these basic ones are figured out.

Suggestions appreciated in advance!

[Chuck Uebele]

While I don't know exactly how to resolve this, and I don't know what your art work is like, from my own experience, PS has a very difficult time stitching something that isn't a photo. It can't seem to align graphics. Lines and angles well. I've had to manually tweak and stitch the images.

[mikalj11434475]

I'm stitching photos of artwork on walls. Shouldn't really matter what the photographs are of, so long as the subjects have clear lines and shapes, which they do. I can post screen shots if that matters, but I think it's not a matter of the subject, but of the settings or the inherent limits of PS.

[Chuck Uebele]

That's what I'm saying, it does matter what the subject is. PS really fails with images with strong lines and graphic elements. I don't know why. I would be interested to see what the images are like.

[mikalj11434475]

These shots in landscape mode (like this one) stitch fairly well. 

In portrait mode, which most sequences are, they come out distorted and jumbled. These places are all gone now, so there is no re-shoot.

[Chuck Uebele]

Interesting. Kind of what I figured with the graphic shapes. Lots of same sized squares. You would think that would be easy for PS to stitch, but it just fails. Only suggestion I have is to stitch them manually.