On Monday, 27 August 2018 at 12:11:41 -0700, Hugin developers list wrote: > @ Greg, Panostar:thanks for the detailed responses. > > Concerning the zenith/nadir: the two pictures in question are "horizon" > ones (shot horizontally). > > Concerning entrance pupil/parallax errors, the area that poses > stitching problems spans from 1 to 3 meters approximately from the > camera, and there is no closer object in-between.
Yes, this is typical of parallax issues. They become more severe the closer you are to the camera. > And it is a flat surface. Can even this condition pose parallax > errors ? Absolutely. Each of these pavers appear in a slightly different perspective in each image. > May the parallax errors come from further objects in the scene ? The parallax errors come from the position of the entrance pupil. They affect the entire image, but they're less of an issue with distant objects. > Concerning the exactitude of the control points, these were > meticulously placed and verified : a few to begin with, then more > and more numbered, and then organized following a kind of a > grid. I've arrived at this level of density (more than the pictures > I posted previously), and the algorithm simply overrides the control > points, making seams. You don't need many control points. 10 are probably enough if they're well positioned. > [image: Nbr_1.JPG] <about:invalid#zClosurez> > [image: Nbr_2.JPG] <about:invalid#zClosurez> I tried to align these, but the control point detectors weren't very happy with them. This may be due to the reduced images, which sometimes cause problems. You say that you used an 8mm lens, but you don't say what sensor format, and the images you supplied don't include Exif data. This information is important. Looking at the images, they're clearly full-frame fisheye, which suggests a Four Thirds or possibly APS sensor. I've tried aligning them, but the control point detectors don't like them much. Can you post all the original files (raw if possible, but definitely with Exif data) somewhere? Also your project file (the one with a name ending in .pto) would be interesting. > ... but maybe he has trouble with 8mm lens extreme distortions), to > no avail. I don't see any issue with distortion in your photos, though there's a bit of CA. Fisheye lenses don't distort, they just have a different projection, and Hugin handles that well. I do most of my panos with an 8 mm fisheye lens, and though I have issues with the control point detectors, I'm sure that they're not related to the lens, and they're also not like the problems you're reporting. It would be interesting to hear how you determined the position of the entrance pupil for your lens. Greg -- Sent from my desktop computer. Finger [email protected] for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. If your Microsoft mail program reports problems, please read http://lemis.com/broken-MUA -- A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ --- You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/hugin-ptx/20180828081743.GC5698%40eureka.lemis.com. For more options, visit https://groups.google.com/d/optout.
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