On Monday, 11 July 2011 at 23:55:25 +0100, Bruno Postle wrote: > On Sun 10-Jul-2011 at 17:19 +1000, Greg 'groggy' Lehey wrote: >>> On Sun, 10 Jul 2011 10:22:58 +1000, Groogle <groog...@gmail.com> wrote: >>> >>>> There's more description, including the images, at >>>> http://www.lemis.com/grog/diary-mar2011.php#time-lapse >>>> The resultant images are shown in the diary entry mentioned above. >>>> The original ones are at: >>>> >>>> http://www.lemis.com/grog/Photos/20110330/tiny/Verandah-before.jpeg >>>> http://www.lemis.com/grog/Photos/20110330/tiny/Verandah-during.jpeg >>>> http://www.lemis.com/grog/Photos/20110330/tiny/Verandah-after.jpeg > >> I'll address the rest in answer to your other message.
Sorry for the slow response here. My original mail messages came through with more than 48 hours delay. From the headers, it seems that it was from somewhere within Google. Hopefully this reply will come through faster. > The control point generators are particularly bad at matching photos > taken at long time intervals - The changes in quality and direction > of light are enough to throw off feature matching. This is probably > why Terry needed to delete a lot of 'bad' control points. Agree, but I'm not sure that's the main problem. I've been playing around with these results, and I have come to the following recognitions: - The way Terry did it, creating the control points from the "Images" window, is vastly superior to the way I tried it the first time from the "Assistant" window. - Some of the control points were on plants and leaves which moved from one photo to another. So I thought, it's a simple set of images with some clearly defined control points. Let's do it manually with control points on parts of the house and brickwork. The result? Worse than what Terry got! > If your photos have different focal lengths, then you can 'unlink' > the 'degrees of view (v)' lens parameter before optimisation. This is the "link" box in the And this, I think, is part of the question, though I didn't see any difference between linking and not linking. But it seems that Hugin is relying on the focal length information from EXIF, and in the case of my camera, that information is very inaccurate. The focal lengths of the two images were given as 21 mm (44.72°) and 23 mm (41.18°). The EXIF data will report a maximum of one focal length value between these two--maybe. Maybe there's nothing at all between the two values. If Hugin is relying on this information, there's a good chance that it will be wrong. I suppose I could guess at closer focal length or field of view values, but there must be a simpler way. For the fun of it, I tried changing the focal length spec for the second and third images. I left the first one at 23 mm, but by changing the focal length of the other two. At 22.421 mm, the errors dropped to an average of 0.3 pixel, with a maximum of 0.92 pixel. Wonderful! Unfortunately, the results didn't look at all wonderful. Now all three images have a different size. I'm experimenting further, but it's beginning to look as if the Hugin or the control point detectors need to find another way of determining the relationship between the image sizes than relying on the EXIF data. Any thoughts? There's more information, including images and discussion, at http://www.lemis.com/grog/diary.php#D11-3 , though that doesn't include the change of focal length. I'm continuing to experiment. And since I've messed it up before, you can get bigger and bigger images of any of these by simply clicking on the image. Greg -- Finger g...@freebsd.org for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. See http://www.lemis.com/grog/email/signed-mail.php for more details. If your Microsoft MUA reports problems, please read http://tinyurl.com/broken-mua -- You received this message because you are subscribed to the Google Groups "Hugin and other free panoramic software" group. A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ To post to this group, send email to hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx
