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.
> 
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