- Ancient Times: B.P. (Before Pixels)
- Now: A.P. (All Pixels, All the Time)
- Resolution and Image Fidelity
- Appropriate Image Formats for Print
- Inappropriate Image Formats for print
This chapter is from the book
This chapter is from the book
This chapter is from the book
Now: A.P. (All Pixels, All the Time)
Film has given way to pixels, and we are now beginning to keep our family photos as shoeboxes full of CDs rather than dog-eared color photographic prints. What was once the province of the darkroom became a daylight venture, and the tools of the craftsmen have become available to anyone brave enough to wade in.
Scanners
While early scanners still required highly skilled graphic arts professionals to operate them, they greatly speeded up the process of capturing artwork for color separations. Early analog models used photomultiplier tubes and a daunting array of knobs and buttons to perform the same job that had been done by the huge cameras. The first scanners were petite only by comparison to their gigantic camera ancestors: Many could easily dwarf a Volkswagen. It was necessary to mount artwork on a heavy, clear plastic drum, and then painstakingly ensure that there was no dust or a trapped air bubble to mar the scan. Scanner operators came from the ranks of color-separation cameramen, and their years of finely honed instincts for camera separations translated well to the newer methods. The first scanners still produced film output, not pixels. But the next development was the move to digital capture and storage of image information, resulting in the introduction of the pixel and the advent of digital retouching.
In the mid-1990s, improvements in the capabilities and simplicity of flatbed scanners, coupled with the widespread usage of Adobe Photoshop, led to a major change in the way color separations were performed. It was no longer necessary to mount artwork on cylindrical drums, and the numerous knobs were replaced with onscreen buttons and dialog boxes. The digital imaging revolution was underway. Suddenly, people who weren't sure what color separation meant were making color separations.
As flatbed scanners have become more automated and less expensive, it's relatively easy even for novices to make a decent scan. But the more you know about what constitutes a good image, the better the chance you can create a great image from the pixels generated by your scanner.
Digital Cameras
Today's scanners capture transparencies, reflective images, or illustrations and express them as pixels. But now we're undergoing another revolution. High-end digital cameras now rival—or exceed—the ability of film-based cameras to capture photographic detail. The image captured by the camera is a digital original, so there's no need to scan a print. Of course, the better the camera and the photographer, the better the image. Your mobile phone isn't up to the job.
While conventional camera film—such as 35mm transparencies—must be scanned to be used on your computer, digital camera images can be downloaded directly to the computer and used immediately. Digital photography also cuts out the middleman. Unlike film images, digital images don't have any grain, but an image photographed at low light may tax the resolving capabilities of a digital camera and thus exhibit digital noise.
Consumer point-and-shoot cameras deliver captured images as JPEG, a compressed format. There are degrees of compression, from gentle to aggressive, and you may never notice any visible artifacts betraying the compression. But higher level "prosumer" cameras and professional digital cameras can deliver images in the Camera RAW format, which is subjected to minimal (or no) compression by the camera. While you cannot place a RAW file directly into Illustrator or InDesign, RAW images can be opened directly in Photoshop and saved in another format, such as Photoshop PSD.
In addition to benefiting from minimal compression, RAW files can be color corrected in the Photoshop Camera RAW environment without losing additional information. For example, an image shot under daylight conditions but with the camera's white balance set to fluorescent lighting, can be corrected with one click in the Camera RAW environment without the loss of information that would occur in a Levels or Curves correction.
Camera RAW is a powerful and flexible format; RAW images also take up more space on the camera's memory card, but the advantages are worth the extra heft.
Imaging Software
Once you have captured pixels, it's likely that you'll want (or need) to do something with them. The industry standard imaging application is Photoshop, and for good reason. Photoshop provides controls for color correction that enable a knowledgeable user to achieve results equal to those of a knob-twisting scanner operator. And its retouching tools surpass the capabilities of the original, million-dollar dedicated systems. If you're just beginning to learn Photoshop, you won't lack for educational resources. You could probably build an addition to your house from the books and magazines devoted to exploring Photoshop. You can add Chapter Nine, "Photoshop CS4 Production Tips," to the pile.
Photoshop is arguably the most versatile and widely accepted application for image manipulation, but there are other applications that perform useful imaging functions as well.
Adobe Photoshop Elements (Mac/PC) might be regarded as "Photoshop Lite," but it still packs a hefty arsenal of retouching and color-correction tools. The product is geared toward enthusiasts rather than professional photographers and lacks support for CMYK images.
Adobe Lightroom™ (Mac/PC) is engineered for use by photographers working with raw digital images. It provides sophisticated tools for organizing and color correcting images.
Photoshop.com (Mac/PC) is an online image storage service, offering some image editing features (for more information, see www.photoshop.com).
Apple iPhoto® (Mac only) offers features similar to those in Photoshop Album. Geared toward hobbyists, iPhoto has organizational tools and limited color-correction capabilities, but no support for CMYK. As you might expect, iPhoto is available only for the Macintosh operating system.
Apple Aperture (Mac only) is targeted to photographers working with raw digital files. It provides organizational tools as well as color-correction controls.
These are not the only solutions that exist for manipulating images. There are painting programs, such as Painter™ and Paint Shop Pro® (both from Corel®), which let you easily make images resemble watercolors or oil paintings. There are countless plug-ins that enhance the Photoshop toolset. Imaging tools for consumer and hobbyist photographers increase on a daily basis. However, most of these programs don't offer support for CMYK images, so they're not the best tools if you're preparing images for print.