Harry Durgin did a couple videos on that https://www.youtube.com/redirect?v=11nInNWJHWk&event=video_description&q=http%3A%2F%2Fweeklyedit.com%2Fcamera-profiling-darktable-chart%2F&redir_token=u1328WDSXNhekRzZLid7MbFMgGh8MTUyNzkwMDE0NkAxNTI3ODEzNzQ2
and https://www.youtube.com/redirect?redir_token=x1pQe5b4RXUCYmFePOfoRGWv5Fh8MTUyNzkwMDE4NkAxNTI3ODEzNzg2&v=LufwQZx01gk&q=http%3A%2F%2Fweeklyedit.com%2Fbasecurves%2F&event=video_description On Thu, May 31, 2018 at 6:51 PM, Robin Kramer <kodr...@gmail.com> wrote: > Ah, I also get weird initial color profiles with a5100. I usually try to > match the jpeg. I might try to generate a custom ICC then. I have a color > checker card. I forget what is the best software to do that. > > > On May 5, 2018, at 2:55 AM, Sarge Borsch <sausagefacto...@gmail.com> > wrote: > > > > Regarding the copyrights question: > > The ICC profile that I got as the result of the conversion is 536 bytes, > at least 29 of which are the ASCII name string that is equal to "Sony > ILCE-5100 Adobe Standard". > > It contains only the following tags: > > desc, > > cprt (= "Copyright, the creator of this profile (generated by DCamProf > v1.0.5)"), > > wtpt (1 XYZ tuple), > > rXYZ, rXYZ, rXYZ, (the most important and probably the only part we > actually need — the color matrix), > > and tone response curves which are just straight lines. > > > > As I see, the only thing in the final ICC profile that could possibly be > non-trivial enough to raise copyright questions is the 3x3 color matrix. > > > > > >> On 4 May 2018, at 22:10, Sarge Borsch <sausagefacto...@gmail.com> > wrote: > >> > >> So, I tried to edit an ICC file in a hex editor to put the values from > that website, and, just as expected, got nonsensical results. > >> > >> After that I tried another idea to snatch better color profiles — I > searched the web for Adobe Camera Raw package, extracted the profiles from > it (they are in .dcp format), and figured that it's possible to convert > them to ICC by dcamprof. > >> They seem to work very well — better than the currently built-in input > profiles for sony a5100 in darktable. > >> Now what do you think about the copyright status of these converted ICC > profiles? Can they legally be distributed with darktable, or should I keep > them only for myself? > >> They are a lot smaller than the source .dcc files, probably because > they don't keep nothing valuable except the color matrices. So are 3x3 > numeric matrices copyrightable? > >> > >> If you think these profiles can be officially added to darktable, I may > fix the name tags and submit a pull request. > >> > >>> On 4 May 2018, at 17:14, Sarge Borsch <sausagefacto...@gmail.com> > wrote: > >>> > >>> Hi. > >>> I see that there are measured color responses at > https://www.dxomark.com/Cameras/Sony/A5100---Measurements > >>> Hence the question: is it a good idea to try to take the built-in > profile and replace the primaries with these measured values, in order to > get closer to the in-camera JPEG color rendering? (or are they already > used?) > >>> > >>> I'm asking that because I've noticed that none of the built-in input > color profiles for sony a5100 allows me to get close to the in-camera JPEG > colors. > >>> The 2 of them which are the closest to the correct rendering (that is, > matching camera JPEG, which is quite good when judging by eye) are the > "standard color matrix" and "linear Rec2020 RGB". > >>> Both of them wildly differ from the in-camera JPEG in deep blue > colors: "standard color matrix" causes them to be clipped and to look > really unnatural, and "linear Rec2020 RGB" looks more or less natural, but > the hue is obviously different (blue gets moved to cyan). Hence I started > to wonder how easy is it to get a better color profile. > >>> > >>> I know that ideally this should be done with a color chart, but I > don't have one and don't have spare money for it at the moment. > >>> > >>> Also I can share a shot of the example object (Raw + JPEG) which has > such problematic color if anyone wants to test it, too. > > > > ____________________________________________________________ > _______________ > > darktable developer mailing list > > to unsubscribe send a mail to darktable-dev+unsubscribe@ > lists.darktable.org > > > ____________________________________________________________ > _______________ > darktable developer mailing list > to unsubscribe send a mail to darktable-dev+unsubscribe@ > lists.darktable.org > > ___________________________________________________________________________ darktable developer mailing list to unsubscribe send a mail to darktable-dev+unsubscr...@lists.darktable.org
