It's a good point that DR's obfuscating the EXIF's ISO info breaks the auto feature in profiled denoise. In the denoise (profiled) module, setting the profile to the appropriate ISO by hand (e.g. if a match is found for ISO 800, instead choosing ISO 200 for images made at DR400) should handle this.
Even if it were possible automatically to handle this case for DR200 or DR400, if one chooses DR AUTO, I don't think the EXIF even obscurely records what is really happening with ISO. The DR feature seems better at producing appealing JPEGs in-camera than helping produce great images from raw files. There's something to be said for photographing at DR100 (i.e. with the DR feature off), watching the histogram, and making a DR-mindful image as best one can in post-processing. On Fri, Feb 6, 2015, at 09:32 AM, Marc Cousin wrote: > On 06/02/2015 12:40, Björn Sonnenschein wrote: > > Hi all, > > If DR200/DR400 is used on Fuji X-Trans Cameras like my X-E1, the ISO value > > actually used will be 1 (2) ev steps lower than the one written to the exiv > > files. So ISO 800 with DR400 will show as ISO 800 in the exiv, but actually > > the image was captured at ISO 200. Does the Profiled Denoise module take > > that into account? That tought came up when I was profiling my camera > > today... > I have this same issue with the XE2. The fact is that if you do a DR-400 > picture, it is taken at 200 ISO, but underexposed 2 stops. So in order > to have a correct picture in darktable, I have to raise the exposure by > 2 stops, and modify my basecurve to compensate in the low-light areas. > So effectively, the highlights are at 800 ISO, not 200, as their > exposure has to be compensated for. > > > > > Also, it seems that even with DR100, ISO values above 1600 are in fact > > captured with ISO 1600, so that for example ISO 6400 with DR100 looks > > exactly like ISO 1600 with DR100 or ISO 6400 with DR 400 or DR 200. > > Right too. Over 1600 ISO, Fujis only raise exposure through processing, > so what you get in the RAW is a 1600-ISO picture. > > ------------------------------------------------------------------------------ > Dive into the World of Parallel Programming. The Go Parallel Website, > sponsored by Intel and developed in partnership with Slashdot Media, is > your > hub for all things parallel software development, from weekly thought > leadership blogs to news, videos, case studies, tutorials and more. Take > a > look and join the conversation now. http://goparallel.sourceforge.net/ > _______________________________________________ > darktable-devel mailing list > darktable-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/darktable-devel ------------------------------------------------------------------------------ Dive into the World of Parallel Programming. The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ darktable-devel mailing list darktable-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/darktable-devel
