The RGB Additive Color Model in Software

Maker QR Code JIS X 0510 in Software The RGB Additive Color Model

The additive color model describes color using light, not pigments, and a combination of the primary additive colors Red, Green, and Blue, when combined in equal amounts at full intensity, produces white, not black as subtractive CMYK color does RGB is a common additive color model, and it is not at all intuitive for an artist to use; however, CorelDRAW has different views of the RGB color model that make it easy and intuitive to work with Because a color model only does one thing it shows a mathematical relationship between values that are intangible the visualization of the relationship between Red, Green, and Blue can use any model anyone cares to use, with the goal being to make color picking and color relationships as painless as possible to perform! Figure 19-1 shows the default view of the Uniform Fill dialog When you first install CorelDRAW, it s optimized for print, both with your view of the drawing window, and with the CMYK color model offered on the Uniform Fill dialog If you do Web work and zero print work, this chapter walks you through how to customize your onscreen display and your color choices for the RGB color model

FIGURE 19-1

Let s take these controls in Figure 19-1 slowly and one at a time It s quite likely that a color attribute you re looking for right now can be defined in this dialog

Color Model This selector drop-down list includes CMYK, CMY (as explained earlier, black is more a part of the printing process than a part of the color model), RGB, HSB, HSL, Grayscale, YIQ, LAB, and Registration These models are covered later in this section If you re in a hurry: CMYK should be chosen for in-gamut colors for printing, and RGB is the color model for doing work that won t be printed Color field and Hue slider Here is something tricky, a little confusing, and totally wonderful on the Models tab A model is a representation of a hard-to-grasp thing or idea Simply because the default color model is CMYK, there s no real reason to offer a CMYK color picker to accompany the color model: CMYK is an intangible item a model of it is best represented by what works for the user! Therefore, by default, the HSB color-choosing field and slider are presented to you, even though you re not choosing HSB colors To manipulate Brightness, you drag the little rectangle up or down in the color field To manipulate Saturation, you drag left or right; and obviously you can navigate both Brightness and Saturation at the same time The Hue slider to the right of the color field sets the predominant, recognizable attribute of the color you re picking Users generally set the Hue first, and then play with the amounts of Saturation and Brightness

CHAPTER 19:

Current Color/New Color The color well at the top shows you the current color of the selected object on the page The bottom color well shows you any changes you ve made, and the two together provide a convenient way to compare color changes Components The field at left provides a numerical breakdown of the current color, as expressed in the components of the current color model Therefore, in Figure 19-1, you can see that the current color is an orange, and its CMYK numerical values are C: 0, M: 30, Y: 78, and K: 16 However, these values are not static; in fact when you click on the icon to the right of any value (the icon that looks like a slider), a slider does indeed pop up, and you can adjust the color you want by dragging any component value up or down This offers a more precise adjustment of the filled object s color; you can also insert your cursor into the number field (it s a live field), double-click to select the entire value, and then type in a new value The fields to the right of the current color model fields are a secondary, static readout that gives you the selected color s equivalent using a different color model You set the secondary field through the Options button in this dialog Name The Color Palette, the strip docked to the right of the drawing window, contains colors that are tagged with names such as Desert Blue and Mint Green To quickly search for a preset color on the Color Palette, you can choose from the drop-down list, or begin typing a name in the Name field as you type more characters, the dialog narrows the search If you have a custom palette loaded, you can t search it using the Models tab of the Uniform Fill dialog; you conduct a search using the Palettes tab Add To Palette This button adds the current color you ve created to the Color Palette s default palette You can then retrieve this color directly from the Color Palette at any time without visiting the Uniform Fill dialog This is one way to save a custom color; see Using the Color Styles Docker later in this chapter for a more feature-filled way to save a custom color Options In this drop-down, you can choose Value 2, which sets the fixed Component readout; for example, if you re working with the RGB color model and want to see a color s components expressed in CMYK values, you choose CMYK from the Value 2 flyout The Swap Colors option switches the order of the New and Old colors displayed at the top right of this box The Gamut Alarm feature puts a brilliant highlight color overlay in the color field to alert you when a color you re selecting can be viewed onscreen but cannot be printed to a CMYK printer with complete color fidelity Of course, you won t see the Gamut Alarm if you re working with the CMYK color model, because all CMYK colors are CMYK-legal Last on the Options list is Color Viewers This flyout offers a choice of color selection interfaces for your chosen color model This deserves a little explanation: to represent the components of color models, the various color models necessarily need to be graphically represented in their unique structure Some color models such