if system monitor profile set, can't override in color management settings

[Elle Stone]

If a system monitor has been set, digiKam/showFoto 2.0 beta2 won't allow choosing another monitor profile.

A bug report on this was already made, http://digikam.1695700.n4.nabble.com/Bug-220889-New-problem-with-color-management-td1722685.html, last update a year ago.

I read through the discussion here: http://mail.kde.org/pipermail/digikam-users/2009-December/008944.html, but wasn't able to ascertain what the expected behavior is.

I confirmed with dispwin -I and dispwin -U that uninstalling the system profile makes it possible to select a monitor profile in digiKam/showFoto in the profile tab of the color management settings dialog. Re-installing a system profile grays out the monitor profile selection box.

Feature? or Bug? Gimp allows to use or not use system monitor, if one has been set. Personally, I like the option of being able to overriding the system monitor profile.

Elle

[Gilles Caulier-4]

2011/2/24 Elle Stone <[hidden email]>:

>
> If a system monitor has been set, digiKam/showFoto 2.0 beta2 won't allow
> choosing another monitor profile.
>
> A bug report on this was already made,
> http://digikam.1695700.n4.nabble.com/Bug-220889-New-problem-with-color-management-td1722685.html,
> last update a year ago.
>
> I read through the discussion here:
> http://mail.kde.org/pipermail/digikam-users/2009-December/008944.html, but
> wasn't able to ascertain what the expected behavior is.
>
> I confirmed with dispwin -I and dispwin -U that uninstalling the system
> profile makes it possible to select a monitor profile in digiKam/showFoto in
> the profile tab of the color management settings dialog. Re-installing a
> system profile grays out the monitor profile selection box.
>
> Feature? or Bug? Gimp allows to use or not use system monitor, if one has
> been set. Personally, I like the option of being able to overriding the
> system monitor profile.
>

But there is already an option to use Monitor profile set in X11.
Overwrite it, i'm not sure...

Gilles Caulier
_______________________________________________
Digikam-users mailing list
[hidden email]
https://mail.kde.org/mailman/listinfo/digikam-users

[Remco Viëtor]

on Thursday 24 February 2011, Elle Stone wrote:
(snip)
>
> Feature? or Bug? Gimp allows to use or not use system monitor, if one has
> been set. Personally, I like the option of being able to overriding the
> system monitor profile.

Why would you want to override one profile with another?

'Overriding' the profile set by dispwin could be a bad idea:
dispwin can install a profile that modifies the LUT for the graphicd card,
which corrects all output to the graphics card from all applications. This can
be completely transparent to the applications (as in, "they don't have to know
what happens")
The profiles used by digikam are (I suppose) more like translation tables,
where the program using the profile translates the image data before sending
them to the graphics system.

So, 'overriding' the profile set by dispwin could have one of two effects:
- the LUT profile is disabled, meaning that images from Digikam display
correctly, and everything else will be uncorrected (not what the one
installing the LUT profile wanted, presumably)

- the LUT profile is NOT disabled; then what should Digikam do? Knowing that
both profiles correct assume an uncorrected display, applying the 'digikam'
profile before the LUT profile would give wrong colours on the image, and
correct colours everywhere else (not what the digikam user wants).

This assumes of course that both profiles do their job. If one of them is
wrong, get rid of it...

Remco

_______________________________________________
Digikam-users mailing list
[hidden email]
https://mail.kde.org/mailman/listinfo/digikam-users

[Elle Stone]

Remco Viëtor wrote

on Thursday 24 February 2011, Elle Stone wrote:
(snip)
>
> Feature? or Bug? Gimp allows to use or not use system monitor, if one has
> been set. Personally, I like the option of being able to overriding the
> system monitor profile.

Why would you want to override one profile with another?

'Overriding' the profile set by dispwin could be a bad idea:
dispwin can install a profile that modifies the LUT for the graphicd card,
which corrects all output to the graphics card from all applications. This can
be completely transparent to the applications (as in, "they don't have to know
what happens")
The profiles used by digikam are (I suppose) more like translation tables,
where the program using the profile translates the image data before sending
them to the graphics system.

So, 'overriding' the profile set by dispwin could have one of two effects:
- the LUT profile is disabled, meaning that images from Digikam display
correctly, and everything else will be uncorrected (not what the one
installing the LUT profile wanted, presumably)

- the LUT profile is NOT disabled; then what should Digikam do? Knowing that
both profiles correct assume an uncorrected display, applying the 'digikam'
profile before the LUT profile would give wrong colours on the image, and
correct colours everywhere else (not what the digikam user wants).

This assumes of course that both profiles do their job. If one of them is
wrong, get rid of it...

Remco

_______________________________________________
Digikam-users mailing list
[e-mail]
https://mail.kde.org/mailman/listinfo/digikam-users

I use ArgyllCMS to profile my NEC 2190uxi monitor in its "native", completely uncalibrated state - the graphic card LUTs are not altered and the hardware controls were not used to alter the native color temperature or transfer curves. Loaded or unloaded, the graphic card LUTs are not modified at all.

I made three profiles, a shaper-matrix (-as) for general use, a single-shaper (-aS) for any programs that might choke on a shaper-matrix, and a Lab cLUT profile (-al - not the same thing as altering the graphics card LUTs - the profile itself contains lookup tables). All of my profiles are "good" profiles.

I can't be the only person who profiles their LCD monitor in its native state or has more than one "good" monitor profile.

The only reason I even stumbled over this issue is that somehow yesterday sRGB got set as my system default profile - I have no idea how. I used to use a script to set the atom thingy every time I start my computer, but that was when I was using an ArgyllCMS profile that DID require modifying the graphics card LUTs.

It is an easy enough "feature" to work around, just drop to the command line and issue "dispwin -U nameofprofile" to unload an unwanted profile. So no biggie. But it does mean going in and altering the digiKam/showFoto color management settings every time the wrong system default might get set. And it means keeping a constant lookout for suddenly being shown "the wrong colors".

I like the way Gimp and UFRaw do it - they both give you the option of using or not using the "system monitor profile". And they DON'T alter your previous choice, if a system default was set in the meantime.

That's the real problem, once a system default has been set, digiKam/showFoto don't give you the option of not using that system default. It gets used automatically, regardless of what you might have previously chosen as the monitor profile. So all of a sudden digiKam was using sRGB as the monitor profile and all my colors were off. That behavior - automatically altering the monitor profile regardless of previous choice, and then graying out your option to change it back - seems to me to be undesirable. Especially when some rude program goes and sets a system default behind your back. (I'm thinking cinepaint/oryanos might have been the culprit.)

Elle