For some reason many TV brands are rubbish at setting up their own TVs to deliver great pictures.

In the vast majority of cases when you get a new TV out of its box, the default picture position is to deliver pictures that are ridiculously overblown, with cartoonish colours, excessive brightness, messy backlighting, and sharpness levels set so high that all you see is noise, not detail.

There was a time when we could at least comprehend this, on the grounds that TVs want to look bold and colourful on bright shop floors.

But these days most TVs ship with separate Shop and Home factory preset modes. The manufacturers's wide-ranging lack of comprehension of how to produce great pictures from their own panels is frankly bewildering.

Thankfully you don't need to be a THX-trained calibration professional to make a vast positive impact on your TV's performance. All that's required is a willingness to brave your TV's onscreen menus, and a few minutes - yes, just minutes – to implement the set-up tips described below.

So what are you waiting for? Pick up that remote, and prepare to unlock your TV's true potential. We've used a Panasonic TV to illustrate these steps but you'll find most TVs have very similar menu systems for changing settings.

TV calibration ports
Make sure you check that the TV you want has the connections you need

1. Make sure you're using the right connections

It's amazing how many people still don't realise that different connections deliver radically different picture quality. So here's a list of connection options organised from best quality to worst:

  • HDMI
  • Component video
  • RGB Scart
  • 4-pin S-Video
  • Non-RGB Scart
  • Composite video input

The most important thing to realise here, of course, is that HD pictures can only be delivered by HDMI and component video.

And since the component is an analogue delivery system, HDMI should be your default these days. Even if you're using a non-HD source, such as a DVD player, you should try and use an HDMI if you can, as its digital delivery system invariably delivers the cleanest, crispest images.

At the time of writing 4K is starting to become a big deal. So if you're interested in that, you will not only be looking to use HDMI ports but the very latest v2.0 HDMI ports, which support the greater data bandwidths required by Ultra HD sources. If you want a 4k TV check that its ports are HDMI 2.0.

Panasonic is also putting DisplayPort sockets on its 4K TVs, as these usually computer-based digital ports are also rather handy at dealing with 4K. However, we don't really expect these to enter common usage.

2. Make sure your sources are set up right

Another external issue that can affect your TV's performance is the settings you're using for external sources like Sky receivers and Blu-ray players. So let's look at a couple of the most important points to keep an eye on.

With Sky/Freeview/Freesat HD receivers, we'd recommend that you set the HD Resolution to Automatic rather than the usual 1080i HD default position. This means the box will output HD in HD and standard def in standard def, leaving the upscaling of the latter format to your TV.

This is a good idea because in almost all cases TVs do a better upscaling job than your TV receiver box can.

With Blu-ray and DVD players, we'd usually suggest that you make sure you've got the frame rate output set to 24p for the purest results. The only time you might want to try adjusting this output to 50 or 60Hz is if your TV's motion handling is unusually poor/prone to judder.

Turn off overscanning to make sure you get the full picture
Turn off overscanning to make sure you get the full picture

3. Turn off overscanning

Moving to your TV now, one of the first things you should do to optimise picture quality is check that your TV is reproducing HD sources pixel for pixel, rather than 'zooming' them up so that the edges of the image are pushed off the edge of the screen.

This 'overscanning' process was originally introduced because broadcasters sometimes put image 'junk' at the extremities of the frame. But this rarely happens in the HD age, with real picture information instead filling every pixel of the 1920x1080 HD frame.

So if you leave overscanning on, not only are you losing a little real picture information but you're losing some of the sharpness that only comes with direct pixel for pixel mapping.

Get contrast settings right and the rest will follow
Get contrast settings right and the rest will follow

4. Put contrast first

As far as many TV experts are concerned, contrast – especially a TV's ability to produce believable blacks – is key to overall picture quality.

It provides the foundation for everything else to grow from. Yet it's also the area where many brands come the biggest cropper with picture presets – especially with LCD screens, which struggle with contrast versus plasma and OLED technology.

Many TV makers ship their products with their contrast levels set to maximum. But while this might help a TV's picture look eye-catching on a shop shelf, such high contrast levels generally wreak havoc on a domestic viewing experience.

First, they make colours look unnaturally vibrant. Second, they make peak whites appear stressed and over-dominant. Third, they exaggerate any noise inherent to the TV technology or source image. And finally they make black levels look forced and hollow.

People with plasma TVs should also note that over-contrasted pictures can cause problems with screenburn, where channel logos and other static image elements can eventually leave a permanent shadow burned into your screen.

As a general rule we'd suggest reducing contrast settings to no higher than 70-80 per cent of their maximum for LCD TVs, and potentially even lower for a good plasma set.

Another related point concerns the dedicated contrast or black level boosting/stretching options some TVs have. If you find one of these on your TV, we'd recommend you at least experiment with turning it off. Why? Because many of them simply go too far, becoming so obsessed with making dark parts of the picture look blacker that they 'crush out' much of the subtle shadow detailing that makes dark areas believable and layered.

If dark parts of the picture look like empty 'black holes' with your contrast booster in action, you're probably better off without it.

Dynamic contrast

The majority of LCD TVs further try to boost their contrast performances by using so-called dynamic contrast options that continually adjust the amount of light emitted in response to changes in the image content.

Again, though, we'd suggest treating such features with suspicion, as in many cases dynamic contrast systems can cause frequent brightness 'jumps' with their continual light adjustments.

If you find yourself distracted by this, try turning the dynamic contrast system off. This will reduce contrast, but in many cases (though perhaps not with LG LCD TVs, which have tended recently to struggle to deliver good black levels without dynamic contrast engaged) you may well find the increased stability worth the contrast sacrifice.

Local dimming

One more issue to discuss in this section is local dimming. It's common now for both edge LED TVs and direct LED TVs (which put their lights directly behind the screen rather than around its edge) to adjust the brightness of different parts of the screen independently to suit the demands of the image.

Generally we'd suggest that you leave these features on, though only at their low settings. Selecting a higher setting can often result in the appearance of distracting side effects, such as hollow-looking dark areas and ugly 'blocks' of light around any bright objects that appear against dark backgrounds.

What you're ultimately looking for when trying to get to your TV's optimum contrast setting is the deepest black colour you can get without causing the image to look unstable, uneven, or so dark that all shadow detailing has been crushed out of the picture.

brightness

5. Watch your backlight and brightness

The single most heinous picture preset 'crime' we see is backlight settings put way too high. While this can make the picture look instantly punchy in a bright shop, excessively high brightness is usually wholly inappropriate for a domestic situation.

At least if you're actually in any way interested in watching pictures that look detailed, contrast-rich and naturally coloured.

We've found that the best picture quality with most LCD TVs results from reducing the backlight and brightness settings to between 40 and 50% of their maximum value. This is especially true if you're watching a film in a relatively darkened room.

You can get away with nudging the backlight up a bit above half way if you're watching in a bright environment, but go much higher than that and both colour accuracy and contrast response start to diminish.

Keeping the backlight and brightness levels as low as we've suggested almost always gives you deeper, richer, more natural-looking black colours. It counters LCD's natural tendency to look rather grey when showing dark scenes.

Plasma exceptions

We should note here that we've been talking about LCD technology. With plasma screens you can arguably use slightly higher brightness settings. Plasma produces its illumination on a pixel-by-pixel basis, enabling you to push the image brighter without dark sections losing their integrity.

However, excessive brightness can still damage colour subtlety with plasma, and can also lead to some excessive dotting noise. This is because higher brightness settings can make it harder for individual plasma cells to control their charge levels.

Backlight clouding

With LCD screens there's one more very compelling reason for reining in their brightness and especially backlight settings: backlight clouding.

With edge-lit LCD TVs in particular too much backlight can lead to areas (especially the corners) of dark pictures looking overly bright, making it look like there are vague clouds hanging over parts of the image.

This is one of LCD's most distracting problems, so it's great that you can usually reduce its impact simply by reducing the backlight intensity.