[Scribus] How do I do color correction

[Hal V. Engel]

On Monday 05 March 2007 14:56, Damien Hull wrote:
> Hal V. Engel wrote:
> > On Sunday 04 March 2007 20:48, Damien Hull wrote:
> >> I have a Lexmark C534. The printed colors are not the same ones I see on
> >> the screen. How do I fix this? I'm assuming this has something to do
> >> with color correction.
> >>
> >> I've played around with this in the past. I was told that I can't get a
> >> .icc file for the Lexmark C534. Maybe I should call them.
> >>
> >> I'm hoping someone can point me in the right direction.
> >
> > You don't say what OS you are using.  But you can get profiles for any
> > printer if you are willing to pay the price to get custom profiles made. 
> >  There is someone named Alastair M. Robinson who is active in the open
> > source area that has an affordable custom printer profiling service.  
> > You can find more information here
> > http://www.blackfiveservices.co.uk/profiling.shtml.  You can NOT expect
> > to get correct results in a color managed work flow if you don't have at
> > least an OK profile for your printer model, the paper you are using, your
> > printer driver and the driver settings you are using.  If you are on
> > Windows or a Mac you may be able to get OK profiles from your paper
> > vendor.
> >
> > Hal
> >
> > _______________________________________________
> > Scribus mailing list
> > Scribus at nashi.altmuehlnet.de
> > http://nashi.altmuehlnet.de/mailman/listinfo/scribus
>
> I'm on Ubuntu Edgy. Which is about to be Feisty Fawn in April. I'm not
> sure if that makes a difference.
>
> As I mentioned in one of my posts about color I was able to get okay
> color printing from Gimp. 

This just means that you were lucky.  You really want to be in control not 
just lucky.

> I was also able to get okay color from Scribus 
> using the pdf export option. Although it wasn't as good as Gimp. Not
> sure why. I think more testing needs to be done.
>
> The color correction stuff is more then a little confusing.
>
>     * There should be a .icc file for my printer
>     * I believe there should be a .icc file for my monitor

If you don't have these then your work flow is not color managed.  The reason 
I asked about your OS is that it affects what options you have for 
getting/creating the profiles you will need to correctly do color management.

You can use ArgyllCMS to calibrate your monitors and create monitor profiles 
if you have a supported measurement instrument.  Some of the supported 
devices are fairly inexpensive.  If you don't have such a device then you can 
use LProf to create an OK monitor profile using visual techniques.

For most users it is much too expensive to purchase the measurement equipment 
needed to create your own printer profiles.  The hardware needed for this 
costs more than $700.  So you would need to create dozens of profiles just to 
reach the break even point compared to using a custom profiling service.  

>     * I was trying to use LittleCMS for color correction
>
> I tried to create a color correction file for my monitor but I couldn't
> get Scribus to use it. I'm not sure if I did it right. 

If by LittleCMS you were referring to LProf I can help you with this.  But I 
think it would be best to post your support request over on the LProf 
trackers on sourceforge if that is the case.

> I wasn't able to 
> find a .icc file for my printer. Maybe I need to call the company and
> ask for one. If they don't have one I'll check out the link you posted.
> I hope he doesn't charge a lot.

For an RGB printer profile he charges $25.  This is a very reasonable fee for 
this service.  Some printers will need to be periodically re-profiled because 
they way they reproduce color will vary over time but some printers (for 
example the Epson ink jet printers) have very stable color reproduction and 
can use the same profile for the life of the printer as long as you use the 
same paper stock and driver settings. 

>
> What's this about the paper vendor and color correction? This is the
> first time I've heard of this.

In the last year or two most of the major paper vendors have created web pages 
where you can download profiles for their papers for at least the higher end 
color printers.  This should tell you that color management is now in teh 
process of becoming mainstream.   

Keep in mind that printer profiles are specific to the printer (not just the 
model either but to the specific printer but a generic profile for your 
printer model is way better than no profile at all), the paper, the driver 
(or RIP) and the settings used in the driver.  So it makes sense for paper 
vendors to offer profiles for their papers and a wide variety of printers.  
That way a user can buy, for example, Illford paper and get a profile from 
Illford for say an Epson R2400 and know that the results will be as good as 
using Epson paper with the Epson supplied profiles with in the limits of the 
paper being used.   Of course in most cases these vendors only offer this for 
papers that are of photographic quality and higher end "art" papers.  The 
down side is that so far these profiles are only offered for Windows and Mac 
drivers.  That is none of these would be valid for Linux users using any of 
the available printer drivers.  Which again gets back to the question about 
what OS you are using.  It should also be apparent that a profile supplied by 
the printer vendor is likely not valid for Linux users since it will either 
be for Windows or the Mac in almost every case.

One other thing.  The color management thing has a significant learning curve.  
So if you are feeling a little overwhelmed that is a normal condition for 
someone who is just getting started down that path.  What you will find is 
that as you get farther up the learning curve you will start to get payback 
in the forum of better, more consistent results with less work.  But it will 
make your head hurt for a while before you get there.

Hal