Portable TVs: How we test
More models tested
Flat panel TV lineup
Rapid changes in TV technology mean our traditional biannual test cycle can no longer keep pace with the deluge of new products.
So we 've dramatically increased the number of TVs we test to around 120 a year – 4 times as many as in 2005. Not only are we testing more models but we're doing it faster and more often than before.
Our experts are busy with continuous tests, covering everything from screen reflections to power usage. New results and reviews of all the very latest TVs will be added to the website every month.
Picture quality
Our team of experts find the ideal settings for each set
As well as subjecting our TVs to a barrage of technical tests, we use an independent expert viewing panel to assess picture quality under the same conditions in a dimmed, tungsten-lit room.
Brightness and contrast levels are set as equally as possible and the sets all receive the same-quality picture signal. The same experts take part each time, and we conceal the brand names.
We show a test card and 8 different video clips – each helps the experts assess a different aspect of picture quality, eg a moving train helps highlight problems with panning and movement. We also view the TVs in HD mode via satellite.
Each image is awarded an individual score, and each TV an overall picture score. Picture quality accounts for 40% of the overall test score.
Sound quality
We use a similar mix of technical measurements and expert opinion to assess sound quality.
Our experts listen to, and score, male and female voices, classical music, pop music, jazz and a TV drama under controlled conditions. Benchmark samples from previous tests are used to ensure continuity.
Technical assessments include measuring the characteristic background noise (e.g. a low-level buzzing) and the maximum sound levels from the internal speakers. Sound quality accounts for 20% of the overall score.
Ease of use
Each player is tested by independent experts
Is the instruction manual as clear as the picture? Our ease-of-use experts assess each TV according to a variety of realistic everyday scenarios. Ease of use accounts for 20% of the overall score.
Setting-up
This involves setting-up the TV for the first time, connecting up all the cables and tuning it in. All the models in this report tune themselves, so you don’t have to fiddle around looking for the best reception.
Everyday use
You shouldn’t have to get out the instruction manual to switch the telly on and off, change channel or use the EPG. We make sure everything is as straightforward as it should be.
Advanced use
Assessments include adjustment of picture settings, making recordings via the EPG and setting the child-lock. The design of the on-screen menu systems are crucial.
Lost the remote
You’ve checked behind the sofa but still no luck. There’s nothing for it, you’re going to have to use your TV without the remote control. This nightmare scenario is this basis for our experts’ assessment of the front-panel controls. Common problems we encounter include:
- Poorly written and confusing instruction manuals.
- Cluttered and poorly laid-out remote controls with hard and unresponsive buttons.
- Sockets to the rear and underneath the TV. Tricky to access – unless the telly is wall-mounted.
- Advanced options often hidden deep inside poorly structured on-screen menus.
- Confusing and slow to scroll EPGs.
Power
Modern LCD and plasma TVs can be a drain on the environment and on your wallet. Which? tests the power consumption of each LCD and plasma TV in a variety of viewing modes and estimates the annual running costs. TVs that guzzle power are marked down overall.
Which? experts helped establish the latest international standards for measuring LCD and plasma TV energy consumption and we use these as the basis for our tests. Using standardised video footage power consumption readings are taken in 16:9 (widescreen) mode with the TV settings as delivered.
However, we actually exceed the minimum standard and take further readings for each LCD and plasma TV while using a moving test pattern. We also check everything in 4:3 (old box shape) mode and then do the whole test again, using the optimum picture settings as selected by our expert viewing panel. We then take measurements five minutes and two hours after switching into standby.
To assess the efficiency of any power-saving light sensor we take measurements in three typical living-room environments; bright daylight, dimly lit and, for horror movie fans, in the dark.
Our experts have found that adjusting the settings (see ideal settings for each LCD and plasma TV tested) can reduce power usage considerably. Power use accounts for 10% of the total test score.
Feature check for LCD and plasma TVs
Which? does a full feature check on each LCD and plasma TV – but goes well beyond just ticking a box for every socket found. Our tests often reveal some hidden functionality and nasty surprises.
For instance, Scart sockets on LCD TVs usually support auto-format switching – eg showing standard (4:3) broadcasts with black bands on either side, so the images aren't stretched out of proportion. We check for this on both Scart and HDMI sockets and find some models don’t automatically switch correctly.
When adjusting your LCD or plasma TV for the perfect picture, you may want to tweak the settings differently for Freeview or DVD. Which? tests whether different picture and sound settings can be ‘remembered’ by the tuner, Scart and HDMI sockets.
Features account for 10% of the total test score.
Evaluations
Once we have all our test results in we evaluate the data to determine the total test score. Currently 40% of the total test score is awarded to picture quality, 20% to sound, 20% to ease of use, 10% features/versatility and 10% power use