On the subject of "[hugin-ptx] Re: Builds 2011.2 and beta 2011.4 - access violations," Carlos Eduardo G. Carvalho (Cartola) said:
>Hi Simon, >have you tried some vertical and/or horizontal lines to avoid the wrong >rotation? Yes. I had over 40 defined lines (pairs of control points), some short and some long. >I sometimes have this problem and I think its usually related >to two possible reasons: >- I forgot to use horizontal and/or vertical lines to level the >panorama I started with one of each (horizontal and vertical) in the 'anchor image'. That itself was chosen as best-fit (closest to correct horizontal/vertical alignment with the horizon). The tripod wasn't perfectly level (out by say 1.5-2 deg. max.) as I had to 'eyeball' it. >- I didn't set the lens correctly - I have set a fish-eye lens as >rectilinear. With this I have already spent some hours... I understand. I have a lens file for each 'normal' setting of the lenses I use, and I load this at the start. I've checked with the EXIF data, and it's correct (12mm). Canon specify exactly 1.6 for the 35mm multiplication factor, and this is part of the file too. >Besides that, I usually follow some optimization steps that I think >help to avoid those things. I know each one of us has your own recipe >and many ways can take to a good result. What I usually do is optimize >the horizon ring first, like you already did, but I also do the >following optimizations: > >- Position (y, p, r) >- (y, p, r, v) >- Everything without translation > >And many times I finish with errors much bigger than 2 - but this can >be due to a use of a self made pano head not very well calibrated. What >I do is correct the possible errors on an image editor, for what I use >GIMP. > >One thing I have already noticed also, is that sometimes that spiky >starfish is not so strong, like if only the corners of the images are >part of that, and the pano stitches well. > >Cheers, >Carlos E G Carvalho (Cartola) >http://cartola.org/360 Thanks :-) I have made a little more progress this morning: I deleted the panorama control file and started a new one. - I loaded three images only, of a vertical set, rather than a horizontal ring. - I tried the 'assistant', which correctly found control points, but it inverted all three images(!). - I restored the image orientation to right-way-up, thinned-out the control points, and did get a stitch to work (badly - lots of broken lines). I had to stop there - have to work! The next step is to define some lines, but I'm also going to re-output the three images from Bibble, with Chromatic aberration carefully corrected, in case that helps. Cheers, Simonm. -- Simon D. Muir Landline: +44 (0)117-962-9761 Bristol, Skype (muirsimon) DDI: +44 (0)207-193-4761 United Kingdom Mobile: +44 (0)796-601-2038 -- 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 [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/hugin-ptx
