The quality of color copies generally comes with some sacrifice in speed: The faster you want to print, the worse the copy quality tends to be. There is, of course, also correlation to price. More expensive copiers produce higher-quality copies.
The highest resolution readily available on the market is 2,400 dpi, which is offered on the ApeosPort C7550I from Xerox. This machine prints up to 50 pages per minute. Other machines, including the HP Photosmart Wireless Multifunction Printer/Copier/Scanner, offer similar dpi specs for as little as $200.
The standard designation for resolution in copiers and printers is dpi, or dots per inch. Copiers and printers can print in higher resolution in in color than in black and white (monochrome), although color printing is slower. Most document printing/copying can be done in 600 dpi, and 1,800-2,400 dpi is enough for high-quality photo prints.
Even though color copying generally takes longer than black and white, some copier/printer units have been optimized for color printing and can print as quickly as three pages per second, or 180 ppm. One such machine is the RISO RZ990, introduced in 2005, which can copy 180 ppm at 600 dpi resolution.
High Speed Equals High Cost
Unfortunately, for high-speed machines such as the RISO RZ990, the purchase price increases rapidly. Whereas a machine capable of 30 ppm is easily available for $200, the RZ990, which copies at six times that speed, retails for $22,995--prohibitive for most personal use.
Photo printers can offer higher resolution than photo copiers, because the scanning function is usually the limiting factor in photocopying. Canon's Bubble Jet Printer i850 has resolution of 4,800 dpi, but no copiers are currently available in the same range of resolution. Still, the 2,400 dpi commonly available is good enough for virtually all photo copying, and certainly more than adequate for document copying.