heya, On Wed, Apr 27, 2016 at 6:04 AM, J. Liles <malnour...@gmail.com> wrote: > Group, > > I've recently acquired a camera with an X-Trans sensor, and have had little > trouble generating images that contain areas prone to demosaicing artifacts.
hehe, i know what you mean. > Is anyone interested in these? If so, is there a certain place I should > host/send them? I have camera generated JPG for comparison along with the > RAF files. nice. very interested. if you could put them up somewhere where we could access them for a few days at least that would be great. i know for instance the rawtherapee guys would probably be very interested in this, too. > In playing around I've discovered a few things: > > 1) Color smoothing is mandatory, as fine lines and especially specular > highlights will always generate nasty color artifacts when using the baisc > demosaicing. Seems like a smarter highlight recovery algorithm could help > identify many of these problem spots. i find removing the highest two frequency bands of colour information using the equalizer is often times a good idea. > 2) None of the 'denoise' modules have sufficient parameter ranges to deal > well with the X-Trans files. what do you mean? i think the profiled denoising works very well on fuji cameras. the original paper was written with test data from fuji cameras and i think the noise model matches them better than most other cameras. > 3) When sufficient denoising is performed to remove maze and color > artifacts, the difference between VNG and Markesteijn demosaicing is > indiscernible. agreed. > I have a style preset which can produce images that match the camera JPGs as > far as noise/detail goes (utilizing the equalizer module) at ISO 3200. nice! > Color is another matter, but I've ordered one of the Wolf Faust IT8 charts > to try and make an ICC profile. i used an it8 and the darktable-lut tool (only in git master currently) to reproduce the provia/velvia/astia/classic chrome/monochrome colour settings quite faithfully, using the colorchecker lut module (can share if you're interested, want to publish only once i tested them some more). i also have a reference lut to produce correctly calibrated output, but tested that even less. > (I tried making one using the imaging-resource.com multi target studio > shots, and while the results were OK, they weren't great). > > P.S. Is there any plan to support Fuji's RawExposureBias exif tag? It is > necessary to display high ISO RAF images at the correct brightnesss. is that just a software exposure correction? never heard of it. cheers, -jo ___________________________________________________________________________ > darktable developer mailing list to unsubscribe send a mail to > darktable-dev+unsubscr...@lists.darktable.org ___________________________________________________________________________ darktable developer mailing list to unsubscribe send a mail to darktable-dev+unsubscr...@lists.darktable.org
