Hallöchen! Helmut Jarausch writes:
> On 06/16/2016 01:52:38 PM, Torsten Bronger wrote: > > [...] > >> [...] But can't you just use the Lensfun formula in Octave? > > Of course, I could, but it won't make sense. As one can see in > the table below, the sum of the coefficients is (significantly) > smaller than 1. But if you replace d with 1-a-b-c, and you should get different values for a, b, and c, namely those for which a+b+c+d = 1. > If one compares a raw image which has been processed without lens > correction with the JPEG file coming from the camera, one observes > that the camera enlarges and then crops the image, i.e. it's > clearly visible that the JPEG file has a (slightly) smaller range > of view. Probably, Panasonic does so to cut off uncorrectable > distortions at the boundary of the raw image. As does Lensfun, at least in the ptlens and poly3 models (unfortunately; I'd love to change that). d is the scaling factor. In a sensible model, d = 1. Tschö, Torsten. -- Torsten Bronger Jabber ID: [email protected] ------------------------------------------------------------------------------ What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic patterns at an interface-level. Reveals which users, apps, and protocols are consuming the most bandwidth. Provides multi-vendor support for NetFlow, J-Flow, sFlow and other flows. Make informed decisions using capacity planning reports. http://pubads.g.doubleclick.net/gampad/clk?id=1444514421&iu=/41014381 _______________________________________________ Lensfun-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/lensfun-users
