Image Editing Terminology
Essential Image and Photo Editing Terms for Desktop Publishers
An important part of any commercial brochure, ad and other marketing material are images. Desktop publishers therefore need not only know how to incorporate ready-made images like clip art and stock photography into their page layout, they also need to know how to create their own images and how to edit photos.
Adobe Illustrator, CorelDraw and Macromedia Freehand are popular graphics software programs that allow editing of illustrations and can be used for page layout as well. Adobe Photoshop, Corel Photo Paint and Paint Shop Pro are popular image editors. Regardless of which program one uses (and there are many more, lesser known or very specialized ones), knowing image editing terminology is crucial. Below are essential image editing terms and definitions:
Image and Photo Editing Terms A to Z
Aliasing: Enlarging a bitmap image often produces aliasing or jagged edges, namely making the squares that it is made up of visible. This happens especially for curves and edges which are harder to replicate with squares. The smaller a bitmap image is or the more zoomed out, the cleaner do the edges appear.
Anti-aliasing is the process of smoothing out jagged edges, making an image look less blurry.
Bit depth or color depth refers to the number of bits used to store an image’s individual pixel information. The scale is as follows:
- 1-bit image (21) = 2 colors; black-and-white images
- 2-bit image (22) = 4 colors; grayscale images
- 8-bit image (28) = 256 colors; Web graphics
- 16-bit image (216) = 32,768 colors or HighColor
- 24-bit image (224) = 16.7 millions of colors or Truecolor; with this setting, many real world colors can be replicated quite well but there are still many more.
A bitmap image is composed of pixels in a grid or raster. Because of their fixed resolution, bitmap images are also called fixed resolution images, making resizing a bit tricky as distortion and jagged edges can occur. Common file formats like .gif, .jpg and .tiff are all bitmap formats.
Call out is the part of an image called that identifies it, often pointing to it with an arrow or set in a balloon, box, etc. A pull-quote, a text extract highlighted through a box or otherwise may also be called a call out.
The term clip art refers to all graphic images that are not photographs. Some clip art can be found on the Internet for public use; some can be bought as a package and some may be fully copyrighted, so it is best to check carefully before using any.
CMYK is a color mode that stands for Cyan, Magenta, Yellow and Black. This mode is used for print images that, if they need to be used on the Web, require conversion to RGB mode.
Desktop color separation (DCS) is a today rarely used, enhanced EPS file format. It separates CMYK files into five files: four grayscale images (one per CMYK color) and one FPO file.
Digital resolution: This is a measure for the number of pixels (or dots) in an image or printer. Adobe Photoshop uses pixels per inch (PPI)to measure image resolution and Corel Photo Paint dots per inch (DPI) to measure printer resolution. The idea is the same: the more pixels or blots of ink, the sharper the image.
Dithering: This is what the incorrect interpretation of color is called, for example, if the bit depth varies from image to monitor. A monitor that can only replicate 256 colors will fall short when having to display an image that was made with a millions-of-colors setting. Especially up close, the image might look pixelated, grainy or dotty.
Embedded paths are stored so that outlines or parts of an image can be easily accessed for manipulation of an object, for example changing a background.
Embossing: creating a three-dimensional look with graphics software
Encapsulated Post Script (EPS): EPS files are usually created in illustration software programs as they provide the best (vector) format when printing high resolution illustrations.
Graphics Interchange Format (GIF) is a low-resolution format developed by CompuServ. It is used for Web graphics and other low-resolution images because it uses 256 colors instead of millions of colors, therefore reducing the file size drastically. This format does not work well for large, high-resolution photographs.
Lines per inch (LPI): Printers simulate solid parts of images by actually printing lines of halftones, measured in lines per inch. Therefore, LPI is also called halftone resolution.
Pixelated: A grainy look of images, especially when enlarged, where on can see the individual dots of color.
Pixel is an abbreviation for picture element and refers to the individual dots of an image that one can see on screen.
RGB is a color mode that stands for Red, Green and Blue. This mode is used for Web images that, if they need to be printed, require conversion to CMYK mode.
Tagged image file format (TIFF) is a bitmap graphics format mainly used for saving and printing high-resolution images. Though flexible and allowing the storage of different layers, channels and other image-related information, .tiff files are often large, making them not easy to share.
Vector images are graphics that are based on mathematical calculations rather than pixels or dots. Therefore, they are not dependent on resolution and can be scaled to size without losing sharpness or image quality. They are perfect for logos and similar graphics but not for those images that require a more natural look.
Rather than buying generic DTP manuals that might explain some of the image editing terminology needed, desktop designers might fare better if they study their preferred graphics software well. Most of the programs come with an extensive help section that explains available tools and terminology used. Here’s an overview of the most commonly used desktop publishing terms and definitions and related, of essential DTP paper terms and brochure folding styles.
Example Of An Edited Image
|
What do you think about this article?
More in Writing & Publishing
Latest Articles