ABSTRACT
Inkjet printers Inkjet printers now dominate the printing market and are especially popular with photographers who are using Photoshop. Inkjet printers come in all shapes and sizes from small desktop devices to huge banner poster printers that are the width of a studio. Inkjet printers work by spraying very fi ne droplets of ink as the head travels back and forth across the receiving media/paper. The different tonal densities are generally created by varying the number of evenly-sized individual droplets and dithering their distribution. Hence the illusion of a lighter tone is represented using sparsely scattered ink dots. The more recent printers are also able to produce variable-sized droplets. The Epson Stylus Photo models use six color inks and these are capable of producing an even smoother continuous tone output. The six color inkjets use additional light cyan and light magenta inks to render the paler color tones. The print output is still CMYK (or CcMmYK to be more accurate), but looks smoother because you have less noticeable dot dithering in the lighter areas. But the print times are also slower than the nonStylus Photo models. Inkjet printers are used for all sorts of printing purposes. An entry-level inkjet can cost as little as $150 and is suitable for anything from offi ce letter printing to outputting photographs from Photoshop. And you don’t have to spend much more than a few hundred dollars to buy an A4 or A3 printer that is capable of producing photorealistic prints. Later on in this chapter I will discuss how it is possible to use a printer like this to produce acceptable guide prints for CMYK press color matching. Although inkjets are CMYK (or CcMmYK) color devices, they work best when they are fed RGB data. This is because a lot of these printers use Quartz rendering (Mac) or GD (PC) drivers as opposed to PostScript. These print drivers can’t understand CMYK. So if you send CMYK data to the driver it will convert the data from some form of generic CMYK to RGB before converting the data again to its own proprietary CMYK color.
