Hello again. I ran calibrate.py but it did not give good results: the corrected pictures show dark rings alternating with clear rings, because the interpolation with only three parameters is not sufficiently precise to compensate this type of vignetting. That's why I propose to use a formula with higher degree polynomials. Regards, Louis
> Le 4 déc. 2016 à 17:33, Karl <lens...@northsun.ca> a écrit : > > Whoops, hit send too soon. :) > > As the vignetting appears to be mechanical Lensfun should be able to > correct it, given profiling data. > > I can't find an entry for this lens in the lens database; you're welcome > to submit profiling images to http://wilson.bronger.org/calibration for > inclusion in the database. > >> On 12/04/2016 08:43 AM, Karl wrote: >> Hi Louis, >> >> Greetings from a fellow Pentaxian! :) >> >> As discussed on >> http://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/304092-da-60-250-mod-ff-9.html >> the vignetting for this lens is caused by a mechanical baffle at the >> rear of the lens, and so the vignetting you're experiencing is likely >> not caused by sensor design. >> >> Several people have reported successfully removing or modifying the >> baffle, which fixes the vignetting with little to no reduced image >> quality. Samples here: >> >> https://www.flickr.com/photos/72309835@N02/sets/72157666809541434/with/26902896134/ >> >> >> -Karl >> >> >>> On 12/04/2016 01:42 AM, Louis Granboulan wrote: >>> Dear all, >>> >>> I use a "smc Pentax-DA* 60-250mm f/4 ED IF SDM" on a "Pentax K-1". >>> This lens is not designed for full frame, but its only drawback is a >>> strong vignetting. >>> This vignetting does not show in the viewfinder, it only shows on the >>> sensor, which means it is "pixel vignetting". >>> Pablo d'Angelo's paper does not take into account pixel vignetting, >>> and one consequence is that lensfun cannot optimally correct this >>> vignetting. I can provide example pictures if you want to check this >>> impossibility statement. >>> >>> I propose to work on adding to lensfun the possibility of using >>> another formula, with more parameters (higher degree polynomial). >>> If I do this addition, will it be integrated in the library, so I will >>> not need to maintain a homemade patch? >>> >>> Regards, >>> Louis >>> ------------------------------------------------------------------------------ >>> >>> Check out the vibrant tech community on one of the world's most >>> engaging tech sites, SlashDot.org! http://sdm.link/slashdot >>> _______________________________________________ >>> Lensfun-users mailing list >>> Lensfun-users@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/lensfun-users > > > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Lensfun-users mailing list > Lensfun-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/lensfun-users ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Lensfun-users mailing list Lensfun-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/lensfun-users
