From: aozer@next.com (Ali Ozer)
Newsgroups: comp.sys.next.sysadmin
Subject: Re: NeXTColor Printer -- MAJOR DISSAPOINTMENT !!!
Date: 10 Nov 92 18:33:47 GMT
Organization: Next Computer, Inc.

In article <Nov04.225819.72851@yuma.ACNS.ColoState.EDU> kelley@kiwi.atmos.colostate.edu writes:
>In article <Nov04.203130.60902@yuma.ACNS.ColoState.EDU> Bill Thorson writes:
>>   We have one of the NeXTColor printers and are extreamly
>> dissapointed with it.  It was ordered right when the
>> printer and 3.0 were announced.  Right now we're thinking
>> of sending them it back because it just will not due.
>>   The colors on this printer are all screwed up.
>> Blue comes out purple.  Gray has a red tint.  Yellow and
>> magenta seem to be too deep.  And green seems a little on
>> the dark side.  All images come out both with some wrong
>> colors and way too dark.
>our NeXT color printer is the same way.  i hope that NeXT
>will be able to correct the color output.

Is this bad color output occur when you are printing CMYK colors, Pantone 
colors, or other (RGB, HSB, etc)?  It might be hard or impossible to tell
depending on the app. Which app was this in? Also, are you using coated 
paper?

When you pick a CMYK color (from the CMYK mode of the color panel) you are
picking a device dependent color. Typically the resulting color will be 
darker than what you see on the screen, and it will be different on different
printers.

When you pick an RGB or HSB color, you are picking a calibrated color, which
should print similarly on different printers. Calibrated colors are a feature
of Level II PostScript; so if you are printing on a Level I printer, then
the colors will be printed in a device dependent fashion. The NeXT Color
Printer is of course a Level II printer and shouldn't have this problem.

Finally, when you pick a Pantone color, you get a color whose device dependent
color value is set depending on the output device. If you don't have Pantone
color tables for your printer, then a default CMYK color value will be used.
However, if you do have the tables, then the generated colors should match
those on the Pantone books. NeXTSTEP 3.0 does come with Pantone tables for
the NeXT Color Printer.

To test this stuff, you can go into Draw, and draw two boxes. Fill one
with a CMYK color (CMYK colors have a little gray triangle chip), and fill
another with the same color in RGB. Print the document out on the NeXT Color
Printer; there should be a big difference in the color values, and the RGB
color should be similar to the one on the screen. Try this with different
color values (green, blue, red). Also import a TIFF image and print that out;
TIFF images are automatically calibrated and the results should be close to 
what you see on the screen.

Having said all this, it's important to note that some 2.x applications fail to
take advantage of some of these different color models, or provide their
own mechanisms for color matching with overrides the default ones available
under NeXTSTEP 3.0. In these apps, which Color Panel mode you choose a color
from doesn't matter; RGB, CMYK, and Pantone colors end up looking the same.

Finally, to get the best calibration, you should be using coated paper.
Without coated paper, the black ends up running, and colors appear darker
in all modes.

Ali, Ali_Ozer@NeXT.com
Newsgroups: comp.sys.next.advocacy