I've made two attempts at creating a vignetting correction profile for a wide lens (Olympus 12/2) and both times ended up with overcorrection when testing on real-world images. I didn't have this issue when calibrating the 25/1.8, and wonder: is the use of a flat diffuser over the lens face an inherently flawed method with lenses that cave substantial curvature to the front element? It occurs to me that the distance between element and diffuser is probably twice as much at the edges as at the center. On an opaque object this would obviously result in signifcantly reduced light at the edges, but I don't understand optics well enough to know if this is relevant to the image projected on the sensor through a bunch of glass...
If this is indeed the problem, is there a suggested workaround? I was thinking of taking the shots of the inside of a softbox or something similar, to increase the distance between diffuser and lens. Thanks, jys ------------------------------------------------------------------------------ Developer Access Program for Intel Xeon Phi Processors Access to Intel Xeon Phi processor-based developer platforms. With one year of Intel Parallel Studio XE. Training and support from Colfax. Order your platform today.http://sdm.link/xeonphi _______________________________________________ Lensfun-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/lensfun-users
