COLOR CALIBRATION
FOR ONLINE PRINTING
One of the biggest challenges of
full-color printing is the difference between what you see on a
monitor and the output of an offset press. This is a complex,
multi-faceted problem that has spawned a number of approaches
industry wide to develop technical standards such as ICC and Lab
Color.
CMYK
vs. RGB: The Color Dilemma
Computer
monitors create colors by mixing the light emitted by Red, Green and
Blue phosphor coatings on the screen (RGB). Printers, copiers and
offset presses create colors by combining a series of tiny dots in
four different colors (CMYK) interspersed on the paper to reflect
the desired color tone. RGB creates colors by adding light sources,
whereas CMYK reflects light from an illuminating source.
Regardless
of your settings or your equipment, your screen can only display RGB.
To further complicate things, digital CMYK printing presses
reproduce a limited range of colors; thousands of colors instead of
millions common in modern computers.
Calibrating
for PsPrint
Rather
than become involved in a discussion of the different technical
approaches, we will focus on a practical procedure to get the best
results when ordering from PsPrint: Calibrating your color space to
match our presses as closely as possible.
Depending
on your system, you can use the advanced settings of your display
card or utilities such as Adobe Gamma, an application that comes
with Photoshop. Set your monitor to approximate the color
space of a CMYK space by appearance matching. The subjective
impressions of "memory colors" determine if the results
look acceptable to the human eye. Memory colors are tones that human
perception automatically recognizes — such as flesh tones,
sky, sand and foliage.
PsPrint
CMYK Calibration Card
PsPrint's CMYK Calibation Card includes four printed images of
memory colors. Complete the request
form and we will send you one at no charge. Once you have
received the card, download the images so you can compare your
monitor's representation with the printed results from the same file
run on our presses.
- Download the four digital images
above — beach.jpg, skintones.jpg, sky.jpg and
vegetables.jpg — to your computer. Note that these are
CMYK images and cannot be displayed in your browser. (PC Users:
right-click and select "Save Target As" to download
images; Mac users: Hold down link and select "Download Link
to Disk" to download images.)
- Open each image in Photoshop, if
possible, or another application that accurately converts CMYK
to RGB.
- Adjust the settings of your
screen to match all four images with the printed Calibration
Card images as closely as possible.
Basically, you're forcing your
display to look flat and dull, like the printed sample. Once
your monitor is calibrated to our color space, you can adjust the
color of your artwork for submission. This will be 90-95% accurate,
but should never replace a hard copy proof if you demand color
fidelity.
SOURCE: PsPrint.com
http://www.psprint.com/helpcenter/tipsandtechniques/topics/calibration/index.asp
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