Re: color profiles in gnome color manager and in applications

[Pascal de Bruijn <pmjdebruijn pcode nl>]

On Thu, Aug 4, 2011 at 9:24 AM, Pascal de Bruijn <pmjdebruijn pcode nl> wrote:
> On Thu, Aug 4, 2011 at 1:15 AM, Matthew Miller <mattdm mattdm org> wrote:
>> I've finally gotten around to color-calibrating my display in Linux. I'm
>> thankful that there's all this great software for doing so.
>>
>> However, one thing makes me confused, and I wanted some clarification. This
>> message
>> <http://mail.gnome.org/archives/gnome-color-manager-list/2011-January/msg00002.html>
>> suggests that the corrections applied by loading the device profiles at
>> session startup are just color temperture (and perhaps gamma -- the above
>> message isn't sure, but it seems to from my experience), and that to really
>> _use_ the profiles, they should be enabled in each application.
>>
>> This makes sense to me but I want to make sure it's correct -- color
>> management is so complicated that it seems easy to inadvertently do
>> something wrong and end up with _worse_ results than uncalibrated.
>
> gcm-apply applies the videolut part of the profile at login, which
> gets loaded into Xorg, this is mostly a correction for color
> temperature (you should see your display gets warmer/colder when you
> login), en indeed gamma.
>
> Then your application loads the XYZ matrix from the profile to do
> final corrections, applications do this by using liblcms. So you need
> both parts active for actually accuracy.

Do mind that not all applications do this by default, for example GIMP
has this turned off by default.

Regards,
Pascal de Bruijn