[Digikam-users] Color Mgmt: Nikon D80; Printer Profile use; GAMMAPage

[Heiner Lamprecht]

Hi Ari,

during Christmas, I've read through the PDF guides mentioned on this 
list a couple of days ago.

http://blogs.adobe.com/jnack/2006/12/new_digital_photo_guides.html

They are very interesting, and some of them are dealing with CMS and 
delivery for printing.  I recommend to read them, for this case in 
particular:

"A Color Managed Raw Workflow from Camera to Print"

"The role of working spaces in Adobe applications" (more theoretical 
background)

"Preparing Images for Delivery" (that's more or less your use case)

On Friday 29 December 2006 15:45, Ari El wrote:
>
> Now I am kind of confused on 3), what I am supposed to do with
> the lab's printer profile? As you mention, having the Cam's
> profile and a working profile (and a calibrated monitor) seems 
> enough to generate a tiff for lab printing...in my own
> colorspace. However I've been checking several pro labs (just out
> of curiosity) and they all offer the profiles for their big
> printers, what's the point?

What I understood from the PDFs:

The printers profile is used for soft proofing, meaning a 
screen-preview of the final print.  Normally, the preview will look 
quite bad, compared to the normal display.  But that's the 
difference between the monitor and the printer.

In general, the printer's gammut is a lot smaller than the one of 
the display.  Black is not really black but dark gray, and white is 
light gray or slightly yellow.  The soft proof is used to identify 
those areas of the picture, which would be out-of-gammut of the 
printer.  With this, you can try to manually adjust the colors.

If you don't do this manually, the software in the lab will do this 
for you.  And you will not have a chance to check this before.

Suppose all colors are inside the printer's gammut, and this gammut 
is completely inside the workspace (e.g. AdobeRGB), it doesn't 
matter, what profile is embedded to the image.  Both will have the 
same result.

BTW:  I assume, the D80 is quite similar to the D100 and D200.  I 
tried a lot of raw-converting with both of them.  Unfortunately, I 
can not recommend to use the Linux-tools for converting.  Instead, 
I use the original Nikon software to create tiffs, and import them 
in digikam and convert them to (16bit) PNG.  The result is a lot 
better, especially in terms of sharpness.  Color management is also 
more easy, as the tiff is in AdobeRGB (I configured the camera to 
use AdobeRGB).


    Heiner

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