The Barnes & Noble Review
Many artists and crafters who are fully at home with their computers increasingly miss "art that you can hold in your hand." Others are only just now gingerly tiptoeing into the digital river. Still other folks have long been computer literate, but have only recently become inspired to try the visual arts. In The Arts & Crafts Computer, Janet Ashford has written a wonderful book for all of them.
You can, Ashford says, "have the best of both worlds: digital tools for creating and printing graphic images, combined with the tactile, three-dimensional and handmade qualities of the traditional arts and paper crafts." And this full-color book shows you how.
Ashford tells you the best way to scan a stuffed animal, how to make your computer-printed greeting cards richer and less "computery," and how to combine digital type, scanned images, and found paper to build one-of-a-kind accordion books. You'll learn how to make your own bumper stickers, discover Dover's great CD-ROM of '30s fruit crate labels, and make the most of that cool inkjet iron-on transfer paper.
We've just scratched the surface. This eclectic, fun book completely erases the artificial distinctions between "traditional" and "digital" -- and it's about time!
Bill Camarda is a consultant, writer, and web/multimedia content developer with nearly 20 years' experience in helping technology companies deploy and market advanced software, computing, and networking products and services. He served for nearly ten years as vice president of a New Jerseybased marketing company, where he supervised a wide range of graphics and web design projects. His 15 books include Special Edition Using Word 2000 and Upgrading & Fixing Networks For Dummies®, Second Edition.
Someone once said, "To err is human, but to really foul things up requires a computer." Whether computers will dehumanize art or free up our creative impulses remains to be seen, but these two books are worthy additions to the discussion. Illustrator Ashford's career was completely changed by the computer. The result was six books on computer graphics, including Start with a Scan: A Guide to Transforming Scanned Photos and Objects into High-Quality Art, written with John Odam. In this follow-up, she enters the arts-and-crafts world. She begins with an excellent chapter on understanding digital tools (bitmaps, PostScript, software for graphics, resolution, etc.), then adds sections on working with photos and scans, using type and design, and gathering the art supplies needed for projects. The second half of the book takes computer-generated art and applies it to the making of cards, small books, and other decorative projects. The book as a whole is packed with historic facts (on typefaces, the development of color greeting cards, and the politics of paper) and usable information (on computer safety and the varieties of binding methods). While Ashford has created images solely within the machine, Pollard and Little seek to use computer-generated images only as reference tools for traditional art media. The authors present over 40 demonstrations that show how to use image-editing software to improve one's drawings and paintings. Each of the 30 artists included uses the computer to develop photographs or sketches into fully developed ideas. They combine photos, apply textures, crop, and edit, and they vary perspective, color, and scale as they create studies. After working out compositional problems, each study is used as the basis for artwork in watercolor, pastel, acrylics, or oils. Each of these books can be used with a variety of available graphic programs, with either a Mac or PC/Windows. Both are solid additions to this rapidly morphing field. Copyright 2002 Cahners Business Information.
Read an Excerpt
Understanding Digital Tools Page layout programs
A page layout program is used to create publications-from a flyer to a multipage magazine or book-by making it possible to combine type and graphics and to manipulate the size and position of these elements. Page layout Programs are based on PostScript and use smooth-printing PostScript fonts. But bitmaps created in an image-editing program-such as scanned photoscan be imported for use as illustrations.
PageMaker was the first PostScript page layout program, followed by QuarkXPress, which now is the biggest seller. Adobe acquired PageMaker and also produces a new program, InDesign, designed to compete with Quark.
Some word-processing programs, such as Word and Word Perfect, can also import graphics and create PostScript type and can be used to design pages, but not with as much freedom and ease as in a page layout program.
Hand-drawing with a computer
Once you have a computer and a graphics program, how do you actually draw or paint? There are two ways to draw on a computer-with a mouse or with a stylus.
USING THE MOUSE
"Drawing with a mouse is like drawing with a bar of soap," says John Odam, my co-author on Start with a Scan (Peachpit Press, 2000). The mouse was developed primarily for interaction with icons and while it's possible to draw with it-I do it every day-it's clumsy. If you plan to do a lot of drawing and painting on-screen, you may want to invest in a tablet and stylus.
USING A DIGITIZING TABLET AND STYLUS
A pressure-sensitive plastic tablet, shaped like a rectangular mouse pad, is connected to the computer. You hold a stylus shaped like a pen, and as you draw with it on the tablet, your onscreen tool moves accordingly. The stylus makes it possible to draw more smoothly and to take advantage of your conventional drawing skills. In addition, the tablet is sensitive to the amount of pressure you put on the stylus. The harder you press, the thicker and darker your on-screen mark will be (provided you are using an application that's designed to take advantage of this feature). The natural-media brushes in Painter, for example, work especially well with a pressure-sensitive tablet and stylus, making it almost like drawing and painting with traditional media.
Resolution is a measure of any system's ability to display fine detail, whether it be in a computer or in the human eye. In computer graphics, resolution refers to the number of small units-dots or pixels-making up an image. The more units per inch, the finer the image will be and the more accurate it will look.
Types of resolution
Resolution means different things when applied to monitors, digital images and printers. Taking time now to understand each kind of resolution will help prevent confusion later on and help you get the best results with scanning and printing.
Attached to a computer is a TV-like monitor on which images are displayed. The resolution of a monitor is determined by how many pixels per inch (ppi) are displayed on the screen. Monitor resolution on a PC is generally 96 ppi and on a Mac is generally 72 ppi. (Apple chose 72 ppi because type is traditionally measured in "points," with 72 points to an inch.) These resolutions are fairly low, compared with the 150 ppi to 300 ppi usually used for scanned images, but the quality of an on-screen image depends not only on the number of pixels per inch but on the "bit depth" of each pixel; that is, how many bits of information are assigned to each one. An 8-bit monitor can assign one of 256 different colors or shades of gray to each pixel, but a 24-bit monitor can choose from among 16.7 million. So a scanned photo will look better on a 24bit than on an 8-bit monitor because its colors are more truly represented, even though the number of pixels is the same.
Image resolution (expressed in ppi) measures the number of pixels per inch. The more pixels, the higher the resolution and the more detailed the image will be. Image resolution is usually higher than monitor resolution, but no matter how high the resolution of an image, it will still be displayed on your monitor at either 72 ppi (on a MAC) or 96 ppi (on a PC). You will not see full detail until it's printed by a high-resolution printer.
Printer resolution-expressed as dpi or dots per inch-measures the number of dots of ink the printer lays down on the paper. As you may already know, graphic images are printed by converting their colors or gray tones into a grid of dots. You can see these dots by looking at a printed photo (in a magazine, for example) with a printer's loupe or a magnifying glass. Printer resolution is often higher than image resolution because it can take several printer "dots" to represent one image "pixel."
Areas of confusion
Resolution can be confusing. The terms dpi and ppi are often used interchangeably, even though they have different meanings. Pixels are the smallest units in a digital image, whereas dots are the smallest units in a printed image. Also, a dot is not always the same size as a pixel. So when a 240 ppi image, for example, is printed at 720 dpi on a color inkjet printer, the printer creates very small dots (at a rate of 720 per inch) to accurately represent all the color information in each pixel (which in a 24-bit image could be any one of over 16.7 million colors).
WHAT IS LINESCREEN?
Another variable that effects resolution is "linescreen" or lines per inch (lpi). Linescreen (also called "frequency") is a printing-industry term that refers to the number of lines of dots (both vertical and horizontal) per inch in a halftone screen. A halftone screen is a pattern of dots used to represent the smooth tones of an image. The screen is used to make a printing plate, which prints the small dots on paper where they blend to create a smooth-looking image.
In commercial printing, linescreens range from the coarse 85 lpi used for newspapers (which can be seen without magnification) to the fine 200 lpi used for high-quality color art books. (A linescreen of 133 lpi is considered to be the resolution of the normal human eye.) As computers have come to be used for making halftone screens, a rule of thumb has evolved: Image resolution (in ppi) should equal two tunes the linescreen (lpi) of the printer. (For example, this book was printed with a linescreen of 133 lpi, so I used an image resolution of 266 ppi for most of the artwork.) But the projects described in this book are made using personal printers rather than printing presses. So do we still need to be concerned with linescreen? Yes, because personal printers also create halftone screens at particular linescreen frequencies. For laser printers we should follow the rule and make the image resolution be twice the linescreen. But there's a different formula for inkjet printers, because of the way their dots tend to spread on paper. Follow the guidelines in the sidebar on the right. For more information and guidelines for commercial printing see TheNon-Designer's Scan and Print Book by Sandee Cohen and Robin Williams (Peachpit Press, 2000). ...
Bringing Images Into the Computer
just as real acoustical instruments sound richer and more natural than electronically synthesized sounds, so the art created outside of a computer-either by photography or by drawing and painting-is often richer and more interesting than art created electronically. Bringing these "outside" images into the computer is key to computer graphics sophistication and is done by scanning or using a digital camera.
Using a desktop scanner
A scanner can take a digital "picture" of anything that's placed on its flat glass surface. Flatbed scanners range in price from $100 to $2,000 and some provide adapters for scanning slides. Most come with software for specifying resolution and size and usually include a "plug-in" for scanning directly into an image-editing program, such as Photoshop. Reliable scanners are manufactured by many wellknown companies, including Hewlett-Packard, UMAX, Epson, Microtek and Agfa. Check computer magazines such as Macworld and PCWorld for quality ratings and check the Internet for the lowest prices.
HOW SCANNERS WORK
When you click "scan" in your scanning software, the scanner positions its scanning unit and then moves it slowly across the image-area, under the glass, while lamps containing red, green and blue light shine on whatever original you have placed face down on the glass. The light is reflected onto mirrors which direct it through a lens to a CCD (charge-coupled device) sensor. The sensor translates the light into digital impulses that create a bitmapped image in which the colors in the original are defined by amounts of red, green and blue light, creating what's called an RGB image (see "Understanding Color Models" on pages 22-23).
BASICS OF SCANNING
Scanning modes. Most desktop scanners provide at least three scanning modes. Black-and-white mode is used for scanning simple black-and-white line art or text. Grayscale mode is used for black-and-white photos (which contain shades of gray) and also for black-and-white drawings that have fine detail and shading. Color mode is used for color photos and art work.
Bit depth. Each mode has its own "bit depth," which refers to the amount of information stored in each pixel in the image. For example, the bit depth of blackand-white mode is 1 bit, which means that each pixel in a black-and-white image can be either black or white. Grayscale mode produces an 8-bit image, so each pixel can be any one of 256 shades of gray, ranging from white to black. Color scanning with a bit depth of 24 bits will produce a range of 16.7 million possible colors per pixel, making it possible to reproduce photographs with great accuracy.
Scanning resolution. Some desktop scanners can capture images at resolutions up to 600 ppi and above, but resolutions this high are usually not needed when printing is done on an inkjet or laser printer. To determine the best resolution for your purpose, see "Guidelines for Resolution" on page 17. ...