[argyllcms] Re: Conversion of spectral file to .cie

  • From: Elle Stone <ellestone@xxxxxxxxxxxxxxxxxxxx>
  • To: argyllcms@xxxxxxxxxxxxx
  • Date: Fri, 14 Oct 2016 19:00:27 -0400

On 10/14/2016 02:49 PM, Dp Mailit wrote:

as for RT = dcp profiles are available from Adobe for example as a part of
Adobe DNG converter distribution... the point was that RT users are not
limited to "matrices" from "dcraw" for a long time

At the heart of a DCP profile is a matrix. Where do you suppose the matrix comes from? Someone makes a target chart shot and then uses profiling software to obtain the matrix.

Quoting from the dcraw c-code just above the adobe_coeff table ("otherwise noted" mostly refers to profiles made from target shots submitted by users to the dcraw dev):

    All matrices are from Adobe DNG Converter unless otherwise noted.
void CLASS adobe_coeff (const char *t_make, const char *t_model)

So except for the RT camera input profiles made by RT users (and devs (and darktable profiles made by darktable users and devs, and so forth), it looks like RT profiles (and profiles from any raw processor that uses dcraw to decode the raw files) in fact do use matrices contained in the dcraw adobe_coeff table.

On 10/14/2016 02:52 PM, Dp Mailit wrote:
willing to as you say "screw EULA",
may be you need to actually read that EULA first to understand what it
means to "screw" EULA in terms of running OSX in VmWare on PC/Windows  :-)

> first you have to
indeed you need to invest some effort here, what a bummer !

It would indeed be a bummer if the only way to get a decent general purpose camera input profile were either (1)buy a Mac computer and install RPP, or(2)install VmWare, download OSX, and violate the OSX EULA by installing it in VmWare, and then install RPP.

But many people do make and use (and like much more than the adobe_coeff table matrices) their own general purpose camera input profiles. There are decent commercially available target charts available. Daylight and direct sunlight do make nice full-spectrum light sources even if the light isn't "exactly" D50. The procedures aren't that difficult to follow. You don't need to break the bank buying specialized lighting and laboratory setups just to make a general purpose camera input profile.

Color management and free/libre photography

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