Lensfun and panorama tools have a slightly different lens model, so it isn't always possible to transfer parameters (I'm not sure if there is a converter, it wouldn't be difficult to write one if it doesn't exist).
The idea of optimising a merged project to get more accurate lens parameters should work. There is a tool called ptomerge in the Panorama::Script perl module for merging projects, I'm not sure if it merges lenses, but if it doesn't you can reassign the lens in Hugin. I like the idea of a 'handheld' mode for limiting translation parameters, though since these parameters are unitless I'm not sure how to pick the thresholds reliably. -- Bruno On Thu, 28 Apr 2022 at 02:34, Jeff Welty wrote: > > I have a new camera (Canon G1X mark iii). > > The default lens distortion at the widest angle (15mm) in lensfun definitely > does not match my particular copy of this camera, so I can't export output > Darktable with lens correction. > > I have a dozen or so mini-panoramas with 2 to 5 images each, of which I can > get very good distortion fits with hugin. Same projection is used for all > panoramas. > > One approach is take the average value of each coefficient from each of the > separate panoramas, and update the lensfun data with the average value. I > did a quick check and this appears mathematically consistent. > > Another approach, which I haven't seen in the FAQ, would be to combine the > panoramas algorithmically -- changing the control point numbers and image > numbers so they all remain unique. The panorama view would make no sense, > but I don't think hugin would encounter any problems with that. > > If I did this, I believe hugin could perform a custom optimization and output > a good estimate for distortion coefs based on all the panorama data I have > for a given focal length. Do you think this will work? > > On a side note -- I have yet to use a tripod, I am pretty good at rotating > the camera around the exit pupil. But a little translation can make a big > difference. I hacked in the constrained Levenberg Marquardt method so the > optimization doesn't get lost looking for large translation parameters. This > seems to be working very well. Hard coded to not let Tx,Ty or Tz change more > than +/- .05 from the starting value found when the optimization begins. -- Bruno -- 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/CAJV99ZiycjnOC%2Bx1C6kC-peBCrMDUvuQpQG1fYcefMrJUsOAVw%40mail.gmail.com.
