- Multiple cameras are syncronised to better than 10mS, parallax is not a major concern. The cameras are offsetby about 5cm from each other and therefore the nodal points BUT the nearest object in frame is 30m away!
John,A good question, I dont have a good answer. Points for consideration:1. Each project only has 4 cameras, the processing time to generate the initial stitch is small compaired with the total workflow so I never bothered2. With extreme weight constraints, the cameras are not as well "fixed" as with a standard nodal mount,I perhaps thought this would make the template not so useful, see rig here https://www.dropbox.com/s/od2kznyb1wb4aog/V10-V11.zip?dl=03. I thought (perhaps incorrectly) that the templates would not help with the "usual issues" experienced by this technique.a. The biasing of control points towards the center of the image works for 99% of users but for this work I need tomanually add more points near the horizonb. Removal of many NADIR points that bias the average error, when the horizon errors are most noticable to usersAre you still advocating templates to improve my workflow?
One final question, to help me understand! What has changed between V10 and V11 that means that the "out-of-the-box" stitching performance has got worse (for this UNUSUAL stitck case)?and if I had been using a template for V10, would I not have seen these issues when moving to v11?
> an email to pt...@googlegroups.com
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Comparing PTGui PRO Version 10.0.11 and 11.12 performance as installed using the same set of images:
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Hi Joost,Thanks... here is a link to the images as an example, and also the two screen grabs showing the sharp difference in the results comparing v10 vs v11.
By the way, only the two zenith images were rotated 90°CW - the others were not rotated at all when I converted them from raw to jpeg in Lightroom.Hi Mark,
EDIT. I have just spend an amazing 45 minutes doing what took me hours yesterday... setting v11 on the samyang preset (no idea why I did not see it before) got me near perfect, or "good enough to use" without further tweaking. Very fast and accurate. I still wonder why that worked so well, and why I got such horrendous results using 12mm full frame!

Hi James,
I think the stitching difficulties stem from parallax, although it's
more severe than I would expect.
In any case it's perfectly fine to use viewpoint correction for these
kind of images, as long as the control points are mostly placed on
ground surface. Control points on elevated objects should only be placed
if they are far away from the camera. Just remember to enable viewpoint
correction on all images except one (which will be used as an anchor).
And although VP correction may improve the alignment, it may cause
nearby buildings to appear slanted.
Kind regards,
Joost Nieuwenhuijse
www.ptgui.com
James,
I remember your work from way back.
I have optimized my share of multi camera rigs in my time. I gave
your set of images a go.
I agree with John and I recommend using templates too. Having as
many lens parameters locked in helps.
Label the camera and the position so they are always in the same
order.
Letting the parameters all be optimized may bring down your
errors but often at the expense of introducing weird distortion.
For your images I only got really good results by having
individual lens settings for each of the lenses. I ended up adding
about 140 control points between images to .
For my own GoPro multicamera rig, I created a little holder for
GoPo to center the NPP over the tripod center and rotate the
camera around to create a single row pano to optimize the
parameters precisely. I used the settings from each camera as the
lens settings in my final template. For you I just added a ton of
control points to get best results I could.

For the template I put in average YPR values so when you open any new set of images, even this project they are only roughly aligned.
When I open the 4 images, apply my template and align images I get an average less than 3 and max less than 9
I am only optimizing YPR. My Settings is set to add 25 CP between pairs. After deleting worst I have between 20 and 25 CP between pairs, hardly any CP on the horizon.
I did find Optimizing viewpoint correction helped to further
align the original project but I would only do that when using the
template if you have added extra control points on the horizon
first.
Please try the template on other set of images taken with the
cameras in the same order.
Jim
- I always add extra control points at the 4 horizon seams. Control Point addition in PTGui is frame-center weighted (this has changed for the better over time) but because of camera orientation one part of the horizon is right in a frame corner
This is easily done by drawing a selection in the area and right click to generate control points here.
- All 4 cameras csn see NADIR. If the 4 images are 1,2,3,4 I always remove control points 2+4 and 1+3 leaving 1+2, 2+3, 3+4, 4+1, this seemed to give a better stitch
I actually found leaving these in helped with my results.
Normally I would say you would want to remove these.
- In exceptional conditions (images are not taken at exactly the same time) I remove points that are furthest away from the annticipated stitch lines. This seems to give a better result
This is definitely a good idea, alignment at the seem is all that matters.
- As there is nothing in the foreeground (typically 30m to infinity) I use Viewpoint correction sparingly to try to improve teh stitch. I understand this is NOT what viewpoint correction s there for!
I will often enable it for every other image. Then switch those
to keep and optimize the others. I find this help constrain the
results from getting out of hand.
Thanks for the supportJames
Jim Watters
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James,
I took the template I provided. Added Optimizing Horizontal Shear and reduced the average from 3.6 to 2.8
Toggling through the individual images in Panorama Editor the
nadir looks much better aligned.
Adding Viewpoint correction I got it down to average 1.5 and max of 5
I recommend calibrating each of the cameras. You can do this individually or by putting the rig on a stationary tall pole take a set of images. Just ensure the cameras go back to same spots each time.
When optimizing images. First pass without shear nor Viewpoint correction. Remove worst control points. then if error too high, then enable them.
Jim