How we test.... inkjet printers

A manufacturers’ specifications might tell you a few useful things about an inkjet printer, but if you really want to know how well it will perform there’s no substitute for hands-on testing. Computer Shopper’s suite of print tests is designed to replicate real-world print jobs, from printing quick draft text documents through to photos on coated paper.

The scores we print with each review give an overview of a printer’s performance and are graphed against average scores we’ve calculated from the countless inkjet printers we’ve previously reviewed.

We also subject each inkjet to a wide range of other tests. By the time each inkjet leaves our hands, we’ve studied more than 130 pages of plain paper output and at least 10 photographs.

To find out how quickly an inkjet produces high quality text, we print 50 copies of a formal letter at a suitable quality for formal correspondence. We time how long it takes to print two 10x8" photographs on coated A4 paper, using the highest available print quality settings.

With any photo-orientated inkjet, we make further A4 borderless test prints using very high resolution colour and black and white images. We test the quality and ease of use of any direct printing functions by printing six photos or more directly from a memory card or PictBridge camera.

We perform all our timed tests using the cartridges that are supplied as standard with a printer. If there is an optional photo cartridge, we repeat our photo tests with that installed. Some two-cartridge, six-ink printers have an optional black ink cartridge, which we use to repeat our plain-paper tests.

TESTS

Mono costs

SETTINGS: Manufacturer’s yield figures where available

WHAT IT DOES: This figure indicates how much you can expect each page of black text to cost in pence, including VAT. We search the internet to find the lowest price for the manufacturer’s own branded black ink cartridge. Wherever there is a choice we choose high-yield supplies, which cost more but print more pages, making them better value.

We find the manufacturer’s figures for how many pages the black cartridge will last, when printing a black text pattern that covers five percent of the page with ink. We divide the cost of the cartridge by this figure to arrive at our price per page.

The cost of ink fluctuates, and each manufacturer uses a slightly different method to arrive at its five percent coverage figure, so our cost per page should only be regarded as a rough comparison between printers. The ISO/IEC 24711 yield testing standard, currently in development, will provide a more accurate comparison in the future.

Colour costs

SETTINGS: Manufacturer’s yield figures where available

WHAT IT DOES: This figure indicates how much you can expect each page of colour text and graphics to cost in pence, including VAT. We search the internet to find the lowest price for the manufacturer’s own branded colour ink cartridge(s). Wherever there is a choice we choose high-yield supplies, which cost more but print more pages, making them better value.

We find the manufacturer’s figures for how many pages each colour cartridge will last, when printing a colour pattern that covers five percent of the page with ink. For combined tri-colour cartridges, the figure is for 15 per cent total coverage, or five per cent coverage per colour. To arrive at our figure we divide the cost of each cartridge by how many pages it will print.

The cost of ink fluctuates and each manufacturer uses a slightly different method to arrive at its five percent coverage figure, so our cost per page should only be regarded as a rough comparison between printers. The ISO/IEC 24711 yield testing standard, currently in development, will provide a more accurate comparison in the future.

Draft speed

SETTINGS: Draft text mode, plain paper

WHAT IT DOES: Inkjets print at their quickest when you only need draft quality. This test is designed to show just how fast you can expect each printer to produce black text, with the results quoted in pages per minute. We print an Acrobat PDF file that contains 50 A4 pages of Alice In Wonderland, timing from the moment we submit the print job until the last page has finished printing. We include the time taken for spooling, as some print drivers prepare the job quicker than others.

This test is conducted at a printer’s Draft setting, provided the results are solid and legible. Where this isn’t the case, we increase the print quality and repeat the test. If a printer has automatic duplex (double-sided) printing, we repeat the test in duplex mode.

Print speed through the looking glass

Normal speed

SETTINGS: Default print quality, plain paper

WHAT IT DOES: The higher you raise an inkjet’s print quality, the slower it will go. This test aims to show how quickly a printer can produce pages of black and colour text and graphics at a presentable quality, measured in pages per minute. We print an Acrobat PDF file that contains 24 colour pages of mixed web content, PowerPoint slides and high-resolution magazine pages. We time from the moment the job is submitted until the last page has finished printing. We include the time taken for spooling, as some print drivers prepare the job quicker than others.

This test is typically conducted at a printer’s default settings, provided the results are solid and free from jagged outlines or excessive banding. Where this isn’t the case, we increase the print quality and repeat the test.

A set of graphics-rich colour pages really tests a printer’s abilities

Photo speed

SETTINGS: Maximum print quality, manufacturer’s own premium photo paper

WHAT IT DOES: Some inkjets make far better photo printers than others, but some take a very long time to print at their highest quality. We test each printer’s photo performance by printing six borderless 6x4" photos onto the printer manufacturer’s coated paper, with the results quoted in photos per minute.

We time the test, which is performed at the maximum available print quality. Any advanced options that improve print quality are turned on.