[scribus] Colour Profiles - make colour matching worse!

John Beardmore John at T4sLtd.co.uk
Mon Jul 27 11:49:52 CEST 2009

Peter Nermander wrote:

>> It would seem logical that if CIELAB is a colour space that can describe
>> anything the human eye can perceive, that all images be stored
>> internally in this format. This then requires a profile that describes
>> the conversion of each input devices colour space to CIELAB, and another
>> profile for each output space describing the conversion from CIELAB to
>> the printer specific output.
> Yes, BUT, image fles would then become bigger. But I think 3x16 bits
> per pixel is enough for CIELAB.

OK, but that might be small price to pay if it made CMS accessible to 
more users. At the moment, complexity makes it less than worthwhile for 
most people.

> That's why images have traditionally been stored with integer RGB
> values. Good old GIF even used a 256 color index to 24 bit colors (so
> even if it supports 24 bit colors, an image can only contain max 256
> of them).

OK, but in the days that the GIF format was conceived 11 meg was a LOT 
of RAM for a PC !

> It is also very unintuitive to work in CIELAB because it is a
> 3-dimensional colorspace, most people prefer to work in RGB because it
> is more intuitive what color component you should adjust to get the
> desired result.

So don't.  You can choose colours in any model of any colour space as 
long as the colours chosen can be represented in CIELAB, which 
presumably should be possible.

Cheers, J/.
John Beardmore, MSc EDM (Open), B.A. Chem (Oxon), CMIOSH, AIEMA, MEI
Managing Director, T4 Sustainability Limited. http://www.T4sLtd.co.uk/
Energy Audit, Carbon Management, Design Advice, Sustainable Energy
Consultancy and Installation, Carbon Trust Standard Registered Assessor
Phone: 0845 4561332   Mobile: 07785 563116   Skype: t4sustainability

More information about the scribus mailing list