Graphic Design/Graphics

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Color[edit | edit source]

Color has three attributes: hue, intensity (saturation), and gradation (value). The two color models are RGB and CMYK. RGB is additive color, and is used by light-emitting devices like monitors and televisions. In this model, white is made up of all colors, and black is the absence of color. CMYK is subtractive color, and is a property of reflective (non-light-emitting) objects, such as paper. In this model, white is the absence of color, and black is made up of all colors. In CMYK, ( Cyan, Magenta, Yellow and Black) Color percentages used determines the color output produced on the Print media.

There are two types of computer graphics: raster (bitmap), such as JPEG (Joint Photographic Experts Group); and vector, such as EPS. These are non-proprietary formats, so they can be read by any vector or bitmap program. For example, if you're creating a file in Adobe Illustrator, and you save it in Illustrator's .ai format, only certain Adobe products will be able to read it. If you save it as an EPS, though, it can be read by other programs, such as QuarkXPress.

EPS (Encapsulated PostScript) supports both vector and bitmap images, and can handle color separations. TIFF (Tagged Image File Format) also handles color separations, but only supports bitmaps.

Clip art consists of small illustrations that are not copyrighted. They are either in public domain, or sold with a user's license.

CMYK AND RGB[edit | edit source]

You must be wondering: what exactly does CMYK and RGB mean and under what circumstances should I use one of the two colour systems? Well, I don't want you to make the common mistakes that most customers sometimes make, so I created this guide to explain the differences between RGB and CMYK colours.

What is the RGB color system?[edit | edit source]

Color mixing with RGB

RGB stands for Red, Green and Blue. The RGB color system uses these base colors to form almost all other colors, because red, green and blue are additive colors. Essentially, this means that the RGB color system creates other colors by combining (or 'adding') different amounts of red, green and blue.

For example, if you want to create the yellow color, just combine green and red. If you want to create the light blue color, you would add green to the blue. Obviously, it's a bit more complicated than it looks and the monitors know exactly how to combine these colors in varying amounts to ensure you get the desired color.

RGB is the color system usually associated with computer monitors and other monitors. LCD/LED televisions also use RGB. Most photographic equipment and digital scanners also use RGB.

The reason why RGB is the standard color system in most digital equipment because it offers a wide selection of colors. By combining the primary colors (red, green and blue) in varying amounts, you get any color with great accuracy. Most photo editing programs use RGB as standard, which is why you need to be extremely careful when developing the artwork for printing (we discuss this later).

What is the CMYK color system?[edit | edit source]

Color mixing with CMYK

CMYK works in a completely different way from RGB colors, because instead of using color "additives", it uses subtractive colors: Cyan, Magenta, Yellow and Key. Key is another name for black.

The main difference is that when you combine all the colors of the RGB color system (red, green and blue) in varying amounts, it ends up in white (i.e., the purest combination). With the CMYK color system, combining all colors, as they are substractive, the darker the colors will be.

For example, if you add 100% magenta and 90% yellow, you will have a striking red. If you combine yellow and cyan, you will have a green color.

Clearly, it works in a completely different way than RGB, as the color combinations are essentially opposite. In addition, CMYK is a four-color system instead of three.

The reason the CMYK color system works is that as it adds colors, the light is absorbed or removed to create various other colors.

CMYK is used by print printers, so if you want to get any printing, you need to be aware of this information.

You can check on the image above, you will first see how different RGB and CMYK are. One of the most notable differences between the two color systems is the way they display the blue color. You will notice that in the image, the main blue color looks different in each image, this is due to the color system.

Generally, blue gets a little more vibrant when presented in RGB compared to CMYK. This means that if you develop your design in RGB and print in CMYK, you will probably see a change in your blue, as professional printers use the CMYK color system.

The same is true of greens, which tend to look a little vibrant and get lost or darker when converted to CMYK.

References[edit | edit source]

«Cores CMYK e RGB – Qual a sua diferença e finalidade?» Sydra Gráfica Online. Consultado em 22 de Junho de 2019