Multifunctional Printers

PRACTICAL ADVICE WHEN BUYING A MULTIFUNCTIONAL PRINTER

A multifunctional printer combines a printer, scanner, copier and sometimes also a fax-machine into one simple unit. This is very convenient as it frees up valuable space on your desk and also saves money as the all-in-one machine costs less than three or four separate machines do.

Printer
The printing quality of all printers has improved considerably in recent years, and at the same time prices are getting lower. Color printouts are no longer a luxury reserved for the most advanced printers. If you own a digital camera, there are even printers that can read directly from the memory card, making it unnecessary to first transfer the pictures to your computer.

Type of printer
The main categories are: - laser printers and ink-jets. Laser and LED/LCD printers produce very high quality text and graphics, the only difference being that the latter two use liquid crystals or light-emitting diodes rather than a laser to produce an image on the drum. Ink-jet printers also produce high-quality text and graphics by spraying ink at a sheet of paper.

Ink jets
Ink-jets work by spraying ionized ink onto sheets of paper. This is achieved by using magnetized plates which direct the ink's path onto the paper in the desired pattern. Recently becoming increasingly common is the two-cartridge system which involves one black and one color cartridge with cyan, magenta and yellow. This can produce 16 million different color combinations. The most common systems today use two ink cartridges, one for black and one for cyan, magenta and yellow. This results in a waste of precious ink as the cartridge needs to be replaced when just one of the colors is used up. The best choice is a printer with separate ink tanks for each color as this reduces the amount of ink wasted. The downside is that these printers tend to be a bit more expensive than those only using two ink-tanks. Today there are printers with new pigment-based ink that gives archive-constant printouts that are water resistant.
 
Ink-jet printers are capable of producing high quality print which almost matches the quality of a laser printer. As a rule, ink-jet printers tend to be somewhat cheaper than the laser variety. They also make better portable printers due to the fact they use much smaller mechanical parts. They are however considerably slower. Another negative point is that high quality paper is required to avoid smudging - a problem that doesn't exist with laser printing.

Laser printers
Laser printers operate by shining a laser beam to produce an image on a drum. The beam effectively alters the electrical charge of the drum, which is then rolled through a toner. The charged areas of the drum pick up the toner using electro-magnetism. A combination of heat and pressure then transfers the toner onto a sheet of paper.
 
Sometimes laser printers are called "page printers." This is because entire pages are sent to the drum before the toner is even applied. This makes for very quick printing times, and the supply cartridges tend to last a long time so they can handle large print jobs. Some cartridges can print up to 15,000 pages before needing to be replaced. Another big plus point for laser printing is their resolution, some have a DPI (Dots Per Inch) of up to 2,400. With resolution enhancement this figure can be even higher. Laser printers are a must for very high quality picture printouts. In addition to that they can also print an almost unlimited variety of fonts. Laser printers used to be very expensive, but now the prices for the lower range models are merely double that of a simple inkjet printer. For color laser printers, the prices are a little higher. It is worth noting that there are also two other types of page printers that fall under the category of laser printers - LED and LCD printers. This is somewhat misleading because they don't actually use a laser at all, although the print quality is very similar. The print process is almost identical, but LED printers use Light Emitting Diodes to charge the drum, and the other uses Liquid Crystals.

Resolution
Resolution is expressed in pixels (points) per inch -the higher the resolution the finer the print quality.

Compatibility
Which operating system can the printer work with? (Some printers can handle both Windows and Macintosh as well as Linux operating systems).

Scanner
The primary function of a scanner is to allow the direct transfer of graphics and printed text to a computer system. The process involves dividing an image into a grid of boxes. Each box is known as a 'bit', and combined the grid is referred to as a 'bit map', that is stored as a file that can then be viewed on a computer screen.

Resolution
The quality of the scan is determined by the optical resolution the scanner provides. The resolution refers to the sharpness and clarity of an image, represented in dots per inch (dpi). The more dots per inch, the higher the resolution and the clearer and sharper the scan. For example, 600 dpi means that there are 600 dots across and 600 dots down, so there are 360,000 dots per square inch. Typically, scanners support resolutions of from 72 to 600 dpi.

Color Depth
Another factor to consider is the color depth capacity of the scanner, which allows the scanner to distinguish the range of different colors and shades in the documents to be scanned. Each point in an image is called a pixel (short for picture element), and different scanners read the pixels in varying intensities of bits. The greater the bit depth, the more colors or greyscales can be represented, and the greater the resolution. For example, a 24-bit color scanner can represent 2 to the 24th power (16.7 million) colors.

Technology
Flatbed scanners On a flatbed scanner, the document to be scanned is placed on top of a glass surface. Flatbed scanners are generally considered the most versatile, as they enable you to scan a range of documents or objects regardless of their size or thickness (e.g. magazines, books, maps, charts, etc)
 
Sheet-fed scanners On a sheet-fed scanner, the document is pulled through the scanner. These are suitable for scanning single sheets of paper, however, the materials that are scanned need to be detached from the book or magazine. These scanners look similar to a portable printer, where the item to be scanned in is fed into the scanner.

TWAIN
Scanners are generally sold with specific operating software that controls the scanning process and adjusts the scanned image. In most cases, this software, called a TWAIN driver, is easily installed on your computer and allows you to use the scanner with other applications.

Copier
The copy speed and resolution are generally the same as the printer speed and resolution.

Reduction/enlargement ratio
Digital copiers are capable of a much larger zoom range (both reducing and enlarging) than analogue machines. A few enlarge as high as 800 percent, but the majority enlarges to 200 or 400 percent.

Fax
Fax machines provide an easy way to send documents over phone lines. Faxing is a faster option than regular mail and an affordable alternative to overnight delivery.
 
A fax machine scans each outgoing page and converts the images into a series of light and dark dots. This pattern is then translated into audio tones and sent over regular phone lines. The receiving fax machine "hears" the tones, pieces the grid together, and prints the total compilation of dots. The result is black and white copies of the original pages.

Modem speed
The majority of fax machines transmit at speeds of 14.4 kbps or 33.6 kbps. 14.4 kbps means a sending time for a single page of six to ten seconds, and about three seconds per page with 33.6 kbps.
 
The high speeds are only available when transmitting to machines that have the same protocol, but the machines are equipped with a fallback mechanism that lets them send and receive at 9.6 kbps to ensure backward compatibility.

Memory
Memory enables a fax machine to store incoming or outgoing pages without relying on paper. The amount of memory required to hold a page depends on the density of the image. In general, you can expect 512 kilobytes to hold about 20 pages to 25 pages.

Speed dials
This indicates how many fax numbers you can store in the memory of the fax machine.