On Friday, March 4, 2011 6:27:13 PM UTC-5, kfj wrote: > > > > On 4 Mrz., 20:36, xraycrystallographer > <xraycrysta...@gmail.com> wrote: > > > One thing that I remain “fuzzy” on is the optimization process using > > the control points. From my playing around it appears that an > > increase in the number of control points results in a better fit of > > the i
> Let's put it this way: if you're working with a good panorama head, a > well-calibrated lens and make no mistakes, you can get away with as > little as two control points per image, because then you just have to > nudge the correct data into the right spot. > > If you're using an uncalibrated lens freehand, generating lots of > control points may give you what looks like a better fit, but in fact > it's just massaging your data within the degrees of freedom the > mathematical model permits. It's cheeting - but you may get away with > it. > > ...snip > > Kay This helps! I think this means that I need to do an accurate lens calibration--I assume the instructions in the tutorial are still valid? I am in the process of building a panorama head (based on a theodolite base) and recognize how important camera position is. This brings up another question. With my home-built panorama head I can read the yaw to better than 30" of a degree. I note that in general the scatter in the yaw angles differs by quite a bit more than I would expect--some times +/- 1degree or more from the actual angle. Would I be better off fixing the yaw at the set angle? I realize there is probably some slop in things like the lens fitting on the camera etc., etc., etc., but I should be able to fix most of these. I should point out that the stitching errors are already quite small. I have taken several 45+ image panoramas and have to really magnify to see the small glitches. I am probably just being too picky! The reason I need the accuracy is that I am trying to convert 2D spherical panos to 3D anaglyphs (see http://xraycrystallographer.blogspot.com/2011/03/new-courthouse-imagej.html). I have to do a significant amount of editing masks in order to do so, so I try for the best possible starting point! Thanks again for the info. John -- 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
