Re: Adding printer profiling support

[Milan Knížek <knizek confy volny cz>]

Pedro Côrte-Real píše v Pá 19. 02. 2010 v 13:01 -0800:
> And Alastair Robinson's (of PhotoPrint fame) opinion on it was to try
> different profiles there:
> 
> http://www.freelists.org/post/argyllcms/Printing-using-an-ICC-profile,3
> 
> It could be that we can actually get away without -S for a decent
> default. We should probably start a thread in the argyll mailing list
> about what to use as sensible defaults for profiling printers (and
> monitors/scanners/cameras too maybe).
> 
I completely agree to get some hints from argyllcms mailing list users.

Also, sooner or later, GCM would need to solve the problem of a general
photographer (I  do not want to know how things work but still want my
pictures nicely printed). A good example is here:

http://photo.net/digital-darkroom-forum/00ViCO

William Palmer wonders what to do to solve the problem that printed
images look fine on direct sun-light, but when hanged on the wall
inside, they look "dark". At the end, Andrew Rodney mentions some
"advanced profiling solutions", which can compensate for different
viewing conditions, but William does not get the point (which is
understandable).

That is what ArgyllCMS takes care by -c and -d parameters for colprof:

--
Since appearance space is used in the gamut mapping (just as it is in
collink), the viewing conditions for the source and destination
colorspaces should really be specified. The source colorspace is the
profile specified with the -s or -S flag, and the destination is the
profile being created. The -c and -d options allow specification of
their respective, associated viewing conditions. The viewing condition
information is used to map the profile PCS (Profile Connection Space,
which us either XYZ or L*a*b*) color into appearance space (CIECAM02),
which is a better colorspace to do gamut mapping in. The viewing
conditions allow the conversion into appearance space to take account of
how color will be seen under particular viewing conditions. 
--

I do also not think that exposing the colprof parameters to a user is a
good idea.

Nonetheless, how about asking the user - "Will your print be viewed in a
dim light environmnet?" "Will it hang in a room well lit by daylight?")

And similarly for "-g" paramater of targen: "Do you print black and
white photographs and want a higher emphasise on grey neutrality then on
colour fidelity?"

Using such questions, the user could be navigated to get a good profile
for his own use.

Regards,

Milan Knizek
knizek (dot) confy (at) volny (dot) cz
http://www.milan-knizek.net - About linux and photography (Czech
language only)