Katharine Thayer (kthayer@pacifier.com)
Mon, 25 Jan 1999 06:33:41 +0000
FotoDave@aol.com wrote:
>
(cut most)
>
Why do you always link everything that has the
> letters CMYK to the question of whether K is to be used.
>
> Dave
In my earlier response, I was responding as much to the vehemence of
your post as to the substance of it, and left one more point maybe not
sufficiently clear. My concerns about CMYK do relate specifically to K,
of course, that's why I keep coming back to it. If you want to use CMYK
without K, then the problems of the altering of the CMY values to
compensate for K don't apply.
On the other hand, I don't get why you would use CMYK if you weren't
using K, because as I said before, K is the whole point of CMYK. Oh,
maybe it's because you can get separations by pressing a button. That's
a plus, I suppose, but I like to see the channels, like to look at them
and work with them as individual negatives, like to see what I've got
before I spend the materials to print them.
And further, my concern isn't for folks like you who understand the
color models; it's for beginners who get a scanner and a copy of
Photoshop, scan in a picture and change it to CMYK and output
separations without understanding the assumptions of the default
settings, which are based on the properties of printing presses and
printing inks rather than the properties of watercolor pigment and gum
or the principles of photography. I've had the feeling that people
didn't always understand that when they change the file to CMYK, the CMY
values are adjusted in a way that's not straightforward, to keep the
density of the pixel the same as black is added. I've had the feeling
that some believed that the RGB values were simply converted straight
across to CMY and black was simply added, adding density to the file,
which is not the case in Photoshop. I just wanted people to understand
in a very rudimentary way the underpinnings of the CMYK color space.
Understanding it, they are free to go ahead and make default CMYK
separations if they want, of course, if it gives them the result they
desire.
Katharine Thayer
This archive was generated by hypermail 2.0b3 on Sat Nov 06 1999 - 10:06:44