Lab

Photo inkjet printers

Inkjets are the standard choice for printing at home. Today's models combine high-quality document output with the ability to print images that rival commercial photo prints, all at a reasonable price - at least until you start buying ink.

They work by firing tiny droplets of ink through a print head onto the page. Ink is fed to the print head from cartridges. Some printers have the head built in, while others, such as HP's D7160, include it in the cartridge, so it's replaced along with your ink. In the past, integrated print heads caused problems if the printer was left unused, as ink could solidify inside the nozzles. But modern inkjets have self-cleaning routines to clear ink from the head, dissolving it with fresh liquid ink.

Print quality is determined in part by resolution: the number of dots the printer can place in each square inch. The number required is very high because the printer has to reproduce the whole spectrum of colours using just a few inks. That means combining lots of dots in the right proportions to create just one pixel in an image. A photo needs to contain about 300 pixels per inch to output sharply, but to print these the printer will need to place thousands of dots per inch.

Inkjet resolution is given as two figures, across and down. The print head moves across the paper to print a strip at a time. For the highest possible resolution - mainly for top-quality photos - it may need to move across the same strip more than once, taking longer to complete a page.

Running costs

During the life of your inkjet, you'll spend a lot more on ink than on buying the printer. In the table on page 70, we've listed the lifespan of all the printers' cartridges and worked out how much it'll cost to print a standard page. These document pages use less ink than a full-page photo, so don't rely on the figures absolutely, but they allow you to compare printers against each other. Remember you'll also need paper; glossy photo paper will cost several pence per page. Try the manufacturer's own paper, as it's designed for the best results, but it's worth experimenting with other papers too.

Inkjets use a variety of ink systems. The most basic involve a single black cartridge and a combined colour cartridge containing the standard printing colours: cyan, magenta and yellow. The colours are rarely used in equal quantities, so one will run out before the others, which will then be wasted when you replace the cartridge. One way to save money is to buy high yield cartridges, which are slightly more expensive but print a lot more pages. We've based our printing costs on these. You can also buy third party cartridges, not made by the printer manufacturer but sold as compatible. Decent ones should work fine, but you can't usually expect prints to look quite as good or last as long as with official cartridges.

Other printers use four to six separate cartridges, which is more efficient but not necessarily cheaper, as a full set often costs more. The photo-oriented Epson and HP printers on test use six separate inks, including light cyan and light magenta, while the Canon PIXMA iP4500 has two black inks, one for text and the other for photos.

For our qualitative tests we print documents including letters, magazine pages, presentations and web content as well as photos, and evaluate contrast, shading, skin tones and colour accuracy.

Inkjet printers are still relatively slow. Luckily, some of the highest-quality inkjets in this group also turned out to be among the fastest.