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CONVERT RGB
color mode to the CMYK color mode before printing !
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When you convert images from the RGB color mode
to the CMYK color mode, you shift them to a smaller color space, and this results in a loss of color information.
The color of your RGB image may change noticeably.
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COLOR MODEL
A method for representing color. Colors can be described
using several different color models. Color model is chosen according to the preferred output method used, i.e..,
on-screen display or printable media. |
| RGB |
Red, Green and Blue |
| CMYK |
Cyan, Magenta, Yellow and Black |
| HSB |
Hue, Saturation and Brightness |
| RGBA |
Red, Green, Blue and Alpha |
| LAB |
Luminance and two chromatic components:
A - green to magenta
B - blue to yellow |
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The following color palette samples are "screen-shots"
of same color swatches* in two of the most commonly used color models, RGB and CMYK.
*Swatch
One of a series of solid-colored patches used as a sample when selecting color. A printed booklet of swatches is
called a swatchbook. Swatch also refers to the colors contained in the Color Palette.
RGB Color Palette
RGB model creates colors by adding light, it is called
an additive color model. Art of reproducing color by adding 3-primary RGB-colors in varying proportions
is called ADDITIVE mixing.
CMYK Color Palette
CMYK color model creates colors by absorbing light,
it is called a subtractive color model. CMYK-model is narrower than RGB. When RGB is converted to CMYK, colors
seem to be "dirtier" and not so luminous. CMY are the 3-primary colors used in SUBTRACTIVE mixing.
When CMY-colors are mixed, it produces BLACK or COMPOSITE BLACK (CMYK).
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HSB color model approximates the way the human
eye perceives color. In the HSB model, color is defined by three components: hue, saturation, and brightness. Hue
determines color (yellow, orange, red, etc.); brightness determines perceived intensity (lighter or darker color);
and saturation determines color depth (from dull to intense). In the HSB color model, Hue (H) is expressed as a
degree of rotation on a circular color wheel. Saturation (S) and brightness (B) are expressed as percentages of
full intensity.
RGBA model is used by Microsoft Image Composer (red, green, blue, and alpha) color model, which includes
transparency information on the alpha channel.
LAB or Lab (CIE L*a*b) is a color model created by the Commission Internationale de l'Eclairage (CIE).
It contains a luminance (or lightness) component (L) and two chromatic components: "a" (green to red)
and "b" (blue to yellow). The Lab color mode is based on the Lab color model.
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MATCHING OF COLOR MODELS
It is a good idea to convert your graphic from its original
RGB mode to CMYK before you print.
To match RGB - screen colors into CMYK - print colors, it is necessary to use an intermediate step that
is LAB - color system. |
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| 1. |
CMYK
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> |
LAB |
> |
RGB |
| 2. |
RGB
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> |
LAB |
> |
CMYK |
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Computer screens display their images using Red,
Green and Blue (RGB) light. These colors make for beautiful displays on your screen. Your
computer's monitor produces colors by combining red, green, and blue light. This means that the millions of colors
that your monitor produces can all be described as amounts of red, green, and blue. These three color components
form the basis for the RGB (Red, Green and Blue) color model. Because the RGB
model is based on colors of light, higher RGB values correspond to greater quantities of light. Consequently,
higher RGB values result in lighter colors. When all three color components are at the maximum value, the
resulting color is white. RGB model creates colors by adding light, it is called an additive color
model.
However, if you try to print those RGB files directly, you may be in for an unpleasant surprise, since color
printers put the image on paper with the use of Cyan, Magenta, Yellow and Black (CMYK) inks.
When the colors you see on your monitor are reproduced on paper, they are reproduced using ink instead of light.
The most common method of reproducing color images on paper is by combining cyan, magenta, yellow, and black inks.
These four colors are the color components of the CMYK (Cyan, Magenta, Yellow and blacK)
color model. Usually, each of the colors that make up the CMYK color model are described as percentages
(from 0 to 100).
Inks produce color by reflecting certain colors of light while absorbing others. Darker inks absorb more light.
Because the CMYK color model is based on colors of ink, higher percentages of color result in darker colors.
In theory, when 100% cyan, 100% magenta, and 100% yellow are combined, the resulting color is black. In reality,
black ink must be added to the color model to compensate for the limitations of inks. Because the CMYK color
model creates colors by absorbing light, it is called a subtractive color model.
So if you take the time to convert your files from RGB to CMYK using a commercial application like
Corel and Adobe Photoshop before you print, your final results will be much, much better!
CHECK IMAGE color PROFILE OPTIONS ! (if applicable)
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Any questions or inquiries may be e-mailed to keppanet@hotmail.com.
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