[Digikam-users] Re : Choose another ICC profile for converting pictures

[Martin (KDE)]

Am 07.10.2011 13:06, schrieb Remco Viëtor:
> On Friday 07 October 2011 11:59:19 sleepless wrote:
>> Hi Remco,
>>
>> Could you explain this to me this:
>> If I print from native Windows 7, or from windows XP in Virtualbox on
>> Linux or from Ubuntu, and in all setups choose the same colorspaces, and
>> the same paper and no corrections or whatever I get tree different prints.
>> The only decent prints I get without heavy color adjustments on the
>> source is in my windows 7 setup, (exactly there where I not want to be)
>> with native canon printerdriver.
>> I lost sofar about 50 A4´s testing for a good result on Ubuntu with
>> Turboprint.
>> Is this the proof that different  software interpreted color profiles in
>> there own way, and thus the faillure of colormangement?

Remco was faster than me, so just my small additions.

> 
> First, I don't print at home, the few I need are better done by a local 
> shop....
> And no, I don't think the colour profile is interpreted differently (as the 
> profile only says 'for color (A,B,C) use colour (A+a,B+b, C+c)' )
> 
> That said, there's a number of factors influencing colour reproduction on an 
> inkjet printer: paper type, inks used, amount of ink used, etc. As with a 
> screen, if you change any of these factors, you'll have to adapt your profile. 
> And I bet Ubuntu doesn't use the same driver as windows (so amount of ink used 
> per dot can very well change). The problem here is that you might not apply 
> any corrections, but the drivers will have to send certain settings to the 
> printer. If these differ between drivers, you're out of luck.
> Or you have to start profiling your printer/paper combination, which requires 
> a different spectrophotometer than for screen profiling (and those aren't the 
> cheapest either). 
> Final solution:
> Have a profile made to order:
>  - download a test image (colour patches of known hues)
>  - pick the settings and paper you want to use, 
>  - print the test image, 
>  - send  it to the provider of the test image, who will create the profile and 
> send it to you (against payment...). Have a look in Google ;)
> Once again, such a profile is valid for ONE printer/paper combination, with 
> ONE set of driver settings. Change anything, and you'll have to get another 
> profile... (same as for screen: change any setting there and you'll have to 
> reprofile)

Or maybe a so called poor man profiling:
http://www.argyllcms.com/doc/Scenarios.html#PP1
here especial the part where reading the test chart is done with a
camera or a scanner.

But Attention: This is in no way perfect. But If you own a good scanner
it will be better than using no profile at all.

I for my part don't print photos at home (as Remco didn't). To me the
quality and efford is not worth the money. Choose a shop which supports
colour profiles (local or net). I use fotocommunity-prints (Germany) and
am happy with the results. They profile their machines every day.

> 
>> BTW In Ubuntu systemwide color mangement does not work at all here, no
>> matter which profile I choose, the colors on the monitor never change.

I don't use internal tools for this. I use argyls tools and they work great.

Regards
Martin