[Digikam-users] Re: Color Management Jeopardy

[Marcel Wiesweg]

> I haven't finished exploring the digiKam raw converter. But there are
> three choices for the camera profile: "None", "Embedded", and
> "Custom".

I agree there are rough edges with RAW file color management. One reason is 
that the relevant widget is in libkdcraw, and color management is in digikam.
Second, specifying a single "input profile" falls short if you use more than 
one camera.
Third, as you point out below, the options dont have a good usability.


> "None":
> I assume that "None" means use the default camera matrix in the dcraw
> code.

I agree

> That's the only logical conclusion, and the output using "None"
> is identical with UFRaw output, after adjusting for exposure. The only
> thing is, if you use any "Workspace" color space other than sRGB,
> digiKam doesn't seem to handle the Tone Response Curve ("gamma")
> correctly. (TRCs aren't always a true gamma curve; sRGB doesn't have a
> true gamma TRC; digiKam seems hard-coded to use the default dcraw TRC,
> which may or may not be exactly the same as sRGB - I'm too lazy to
> track down the answer - but the default dcraw TRC is most definitely
> not a true gamma curve.)

Suggestions at what point we need to improve are welcome ;-)

> Martin is correct when he says that the manufacturer's camera profile,
> if you could even find one, isn't likely to work very well when using
> any software other than the manufacturer's own proprietary raw
> rendering software.

Very important point IMO.

> 
> Many people (including myself) do choose to create their own custom
> camera profile because they are not happy with the colors coming from
> the default dcraw camera matrix. My own custom camera profiles are
> simple, general purpose matrix profiles, just like the ones that dcraw
> uses, only the colors are nicer. A lot of people who own Nikon and
> Canon cameras feel that the default dng matrices produce anemic colors
> for these cameras.

What about sharing such profiles? We could easily setup a repository.