There are three things we want to find out when comparing laser printers: how fast they print, how good their printed output is and how much it costs to run them. We have specific tests or calculations to answer each of these.
We run three different print tests to determine a printerâ€™s speed. The first is the 20 page text document, using a variety of different font sizes, typical of an office report or quotation, but without graphics or photo images. We run the test twice, using the same sheets on the second run and printing on their backs. This has a subsidiary function of testing the printer's ability to print on both sides of the paper (manual duplex), without paper jams.
The second test is a five-page document comprising both text and an organisation chart. This shows how quickly the printer and its driver can rasterise graphical images and tests the reproduction quality of several degrees of tint.
Finally we print a five by three inch photo image to see how well the printers reproduce greyscale images.
Image quality tests are subjective, using a small panel of viewers from a variety of backgrounds. They assess the clarity and density of printed text and the regularity of fill patterns and tints. With photographic material, they look for definition and natural reproduction.
Printing costs are calculated as the price of the toner cartridge divided by the number of pages it can reproduce at five per cent cover. If the drum unit in the printer is sold separately from the toner, this is factored in over its lifetime in the same way as the toner. Finally a cost of 0.6p is added for paper.
Total Cost of Ownership (TCO) is calculated as the cost of the printer itself, plus consumables sufficient to print 30,000 pages. Maintenance costs are not included.