Thanks to everyone for their comments, here is a summary of what I've
discovered about this topic:

1) Rule 1--avoid CMYK colorspace as much as possible.  Most color computer
printers prefer to use a RGB input, even though the actual inks used are
Cyan, Magenta, Yellow, and blacK.  The printers have been factory
calibrated to convert the RGB input into a form of CMYK that is best for
the specific inks used on that printer.  Converting to CMYK actually ends
up causing the printer to first convert back to RGB and then back to CMYK
with terrible results.  At least, this is the case on the HP color laserjet
4500 and the Tectronics Phaser dye sublimation printers that we have in the
lab here.

2) I was able to get reasonable results on screen using Photoshop version
6.0 or higher, which I'm told has advanced color processing capabilites.
Again, in light of rule 1, there is little reason for most of us to use
CMYK because we're making images to display on RGB monitors or print on RGB
printers.  Therefore, unless we're graphics professionals who need to
generate CMYK images for print, this is probably not an essential upgrade.

3) The reason for original post is that I have a paper submitted for press
in a scientific journal.  Normally, the journal publisher takes hard copy
from the authors and sends it to the printing company to generate the 4
color separations for press.  Nowadays, many journals have online
submission, allowing electronic transmission of the text and figures which
they pass onto to printer directly.  Since the printer uses a 4 color image
for layout, they ask that you submit the image in the format that they
normally use, which is a CMYK EPS.  In theory, this allows the printer to
save a little time and your paper comes out faster.  In reality this is a
pretty inpractical thing because in order to generate a proper CMYK image,
you have to know the quite a bit about the settings, paper, and ink used by
the printer.  In other words, it is better in this case to generate a
really high quality hardcopy and then mail it to the printer to do the
color separation on their equipment or look for a printer that is smart
enough to convert RGB images into CMYK on their own.

Thanks for the help,
Tom

Dennis Miller wrote:
>I have output to very high end printers directly from BMP files that have an
>RGB color space (Durst Lambda, Fujix Pictography, IRIS). The colors are
>nearly identical to what I see on my monitor. Is there some conversion to
>CMYK that could be done (if needed) on the way to the printer? What printer
>are you outputting to?
>d.
>
>D.

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