Labs

20+in TFTs

At the end of each review, you'll find Image quality, Features & Design, Value for Money and Overall ratings. These aren't simply plucked out of the air; they're calculated using a mixture of objective benchmarks and subjective scores.

Image quality

We begin by connecting each monitor to our eight-way DVI splitter for simultaneous side-by-side comparison. With DisplayMate Multimedia Edition 2 (available at www.displaymate.com), we first use an ANSI setup screen so that eight dark and light shades of grey are visible at once, adjusting each monitor's brightness and contrast until the optimum balance is found.

Next, we display an obstacle course of technical images designed to highlight any potential problems or limitations of each TFT. These include checking for colour purity by displaying full-screen colours, and colour-tracking errors by looking for any colour tints on a series of progressively darker grey squares. Colour and greyscale ramps are examined for stepping - the fades should be completely smooth.

But we're more interested in how the TFTs perform in the real world, and this is where a large portion of the quality scores are awarded. First we look at the quality of the Windows Desktop and Microsoft Office applications, since these are the screens the majority of users will spend most of their time looking at.

While most TFTs pass these tests without major problems, some are truly outstanding, whereas others are merely acceptable. We check the Desktop for the clarity of text in folder icons (which over-bright screens often blow out), the evenness of white areas, any graininess, glare or reflections and overall appearance.

We also view a selection of digital photos, each chosen to expose different attributes such as the shadow detail in a landscape image, highlight detail in an indoor shot with harsh backlighting or skin tones in a portrait photo, and we appraise the overall sharpness and colour realism in each image.

We then play a selection of DVDs and high-definition video clips, chosen for high dynamic range (dark and bright scenes) and for fast movement. We check to see how well the panels reproduce detail, whether they smear fast sequences and whether any artefacts are visible. Finally, we play a 3D game - Crysis - since the fast movement can highlight any response-time issues or problems with internal electronics that appear as colour smearing, blurred edges or tearing.

Features & Design

The Features & Design rating is calculated by awarding points to items such as the video and audio interfaces and warranty cover. The main cover tends to be a three-year on-site swap-out for most TFTs, but some have to be returned to base. For stands, we give points for height, tilt and swivel adjustments, pivoting ability and the width of the bezel (with a view to tilting monitors). We also use a panel of judges to evaluate the quality of any integrated speakers and the overall style of the monitor.

We reward the range of inputs and outputs, penalising any with captive cables. The OSD is an important part of any TFT, so we reward those that are simple to navigate and offer a full range of options. Some TFTs have great OSDs, but are a pain to use, as the buttons are either out of sight, so it's hard to press the right ones, or have such illegible labels that it isn't clear what to press at all.

Value for Money

The Value for Money rating is based on an average of the Image quality and Features & Design scores, with the former weighted slightly higher. We then factor in the price of each TFT (including delivery) to give a bang-per-buck result.

Overall

The Overall score is simply a straight average of the Image quality, Features & Design and Value for Money scores.