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A comprehensive buyers guide for Plasma and LCD TVs - there's lots to consider when choosing the dream television to live at the heart of your lounge room.
Choosing the perfect television for your lounge room requires more than just a ruler. Sure big is beautiful, but the proof is in the viewing.
Screen Size
Before you rush out to buy the biggest television you can afford, stop to think about the space it will live in. The distance between your couch and your screen should be between two and five times the width of the screen. Any further away and you'll start to lose the fine detail, but any closer and you'll be distracted by the individual pixels.
Also think about your home entertainment cabinet - is it big enough to handle your new pride and joy or will it need upgrading as well? Most new televisions are rectangular like a cinema screen, a shape known as "widescreen" or "16 by 9". Televisions are measured on the diagonal, so if you're upgrading from a squarish "4 by 3" set to widescreen you need to go up a few inches if you want the screen to be the same height.
Also give some thought to the layout of your lounge room if you're considering a technology prone to narrow viewing angles, such as LCD or rear projection. Narrow viewing angles can mean the picture appears too dark for viewers not sitting directly in front of the screen.
Display Technology
Flat is the new black when it comes to big screens. Television makers are phasing out bulky old CRT (Cathode Ray Tube) televisions in favour of slimline LCD (Liquid Crystal Display) and plasma sets. They're collectively known as "flat panel" televisions but are sometimes incorrectly referred to as "flat screen" - whereas flat screen actually refers to CRT televisions that don't have a curved screen.
 While the battle between plasma and LCD gets most of the headlines, both still struggle to match the image from a good CRT. Even so, the size and weight of CRTs make it impractical to build them larger than around 37 inches.
If size matters, rear projection televisions go up to around 70 inches but they've traditionally been bulky units with very narrow viewing angles. Rear projection has made significant advances with the move to new projection technologies such as LCoS (Liquid Crystal on Silicon).
As always there are new technologies on the way, with OLED (Organic Light-Emitting Diode) is set to replace LCD, but it has been slow to come to market. OLED doesn't require a backlight so it can offer greater contrast, less motion blur and lower power consumption than LCD. The technology is already used for small displays such as on mobile phones and digital cameras. Of the handful of OLED televisions on the shelves most measure under 20 inches, although 40 inch models have appeared at trade shows and should make it into stores in the next few years. OLED is sometimes referred to as OEL (Organic Electroluminescence).
Active-matrix OLED (AMOLED) screens have appeared on small devices such as smartphones and are also making their way into notebooks and televisions. AMOLED consumes less power than passive OLED.
Other new technologies on the horizon include SED (Surface-conduction Electron-emitter Display), FED (Field Emission Display) and Laser Television.
Resolution
Resolution refers to the number of dots, or pixels, used to make up an image. The two common resolutions of high definition televisions are 1366x768 pixels (known as HD) and 1920x1080 pixels (known as "True" or "Full" HD). Televisions are available at a range of other resolutions including 1024x1024, 1024x768 and 852x480 - sometimes using rectangular pixels to create a widescreen display even though the resolution isn't 16 by 9. If such a televisions can display a downscaled HD signal, it's know as an EDTV (Enhanced Definition TV).
When it comes to high definition, a 1366x768 plasma is roughly the same price as a 1920x1080 LCD of the same size. Considering 1920x1080 is the resolution of Blu-ray, HD DVD and HD television, you'd think that 1920x1080 LCD would be better value for money, but there's more to a good television than just pixels. The proof is in the viewing, for example some high-end 1366x768 plasmas can look just as sharp as a 1920x1080 LCD.
Tuner
The government has introduced a new labelling scheme to help buyers know what kind of tuners are in televisions. The blue "Digital Capable" sticker means it's an analogue television that doesn't actually have digital tuners and can only display the digital channels if you hook it up to a digital set top box. The yellow "Digital Ready - Standard Definition" sticker means the television only has SD digital tuners, while the purple "Digital Ready - High Definition" sticker means you can get all the SD and HD digital channels.
Each of Australia's five main television networks now has a main SD channel (such the Seven Network's 7), which is generally simulcast on a HD channel (such as 70). They also have at least one extra SD channel (such as 72) which broadcasts alternative programming (generally repeats of old shows). The exception is the Ten Network, which offers 10 in SD and a new 24 hour sports channel called ONE, which is broadcast on 1 and 11 in HD and 12 in SD.
Features such as Picture in Picture require two tuners, but some televisions include one analogue tuner and one digital. The analogue tuner will be rendered useless when analogue broadcasts cease over the next few years.
Australian digital television is broadcast in the MPEG-2 format, but the networks may eventually switch to the less bandwidth-intensive MPEG-4 format. If this happens only television equipment with MPEG-4 tuners will continue to work (MPEG-4 is backwards compatible with MPEG-2). Television equipment sporting the Freeview logo has at least one high-def, MPEG-4-compatible tuner. Freeview-branded recorders also have ad-skipping disabled.
Brightness and Contrast
Television brightness is measured in candelas per square metre (cd/m2) and varies from 250 cd/m2 to up past 1000 cd/m2. LCDs are generally brighter than plasmas but anything over 400 cd/m2 should suffice in most lounge rooms. Brightness is important if you'll be watching a lot of television in a brightly lit room, otherwise you should pay more attention to contrast. Contrast refers to the ratio between black and white, for example 1000:1 means the whitest white is 1000 times brighter than the blackest black. Low contrast means your blacks look grey and you lose fine detail in the shadows. Plasmas generally offer greater contrast than LCD, although LCD is improving thanks to technologies such as LED backlights.
Watch out for a form of voodoo mathematics used by LCD manufacturers known as "dynamic contrast". In dark scenes it drops the brightness of the backlight to create blacker blacks, but obviously at the expense of the bright spots in the picture. The difference between the blackest black in a movie's dark scenes and whitest white in the bright scenes is dynamic contrast, but you never see these on the screen at the same time. The difference between the blackest black and whitest white in any one frame is the static contrast. The use of rubbery contrast ratios means the number is only a rough guide to actual picture quality.
Response Time
Response time determines how quickly the pixels in an LCD screen can change colour and is measured in milliseconds. A high response time means fast moving objects, such as scrolling text, are more likely to blur as they race across the screen. Response times were initially measured as the time it took to change from black to white and back again, but today are usually measured as grey-to-grey - the time it takes to change from one shade of grey to another. There are several techniques to improve the response time of an LCD panel, such as "overdrive" which applies a higher voltage to the tiny liquid crystals.
Such tricks are often at the expense of image quality. Most new LCD televisions have a response time under 12ms, but there are so many different ways to measure response times, and so many so tricks to tweak them, that the figure has become almost meaningless.
Refresh rate
The refresh rate basically refers to how often the image on and LCD screen changes and is measured in Hertz. Refresh rates initially corresponded with the frequency of mains power, which is 50Hz in Australia. Doubling the refresh rate to 100Hz helps reduce flickering and motion blur, plus it smooths out the motion in fast moving scenes by creating extra frames. A handful of television manufacturers have released 200Hz models, although the improvement from 100Hz to 200Hz isn't as pronounced as the improvement from 50Hz to 100Hz.
The "Sub-field drive" Hertz rate quoted by some plasma manufacturers, such as 600Hz from LG and 550Hz from Panasonic, is not directly comparable to an LCD refresh rate. Sub-field drive refers to rapidly flash the dots on a plasma panel to prevent phosphor lag. For each frame displayed, the Sub-field drive flashes the dots 8 times or more, meaning that the dots are flashing at least 400 times per second (400Hz). For example, 50 frames per second x 8 sub-fields = 400 flashes per second. Increasing the number of sub-fields increases the Sub-field drive Hertz rate by multiples of 50.
Video Processing
Video processing is the black magic performed behind the scenes that separates the good televisions from the great ones. This 'x' factor is the reason why buying a new television isn't just a numbers game judged by pixel counts, contrast ratios and response times. The proof is in the viewing. Generally any television will look fantastic if you feed a perfect signal into it, such as a 1920x1080p Blu-ray movie.
While giant televisions help high definition look its best, they also magnify any imperfections in the picture, so standard definition material can look terrible. Good onboard video processing ensures DVD, VCR and standard-def television still look their best. Live broadcasts of fast-moving sport, such as AFL, are useful to judge how a television handles a less than perfect picture. Also take along your favourite movie on DVD, something you're very familiar with, and see how it looks on different televisions (using the same DVD player if possible). Look for motion blur, speckles of noise and pixelation - particularly in the shadows. Also watch out for straight lines that become jagged while the camera moves.
Connectors
The most important connector to look for is HDMI (High-Definition Multimedia Interface), the new cable format that combines digital video and audio in the one cable. Most high definition sources, such as Blu-ray/HD DVD players and HD Personal Video Recorders, use HDMI - so you need at least one HDMI input, preferably more.
The HDMI inputs needs to be HDCP-compatible (High-bandwidth Digital Content Protection) for watching commercial Blu-ray movies. DVI cables can also carry high definition video, but require a separate cable for audio. If you'll be connecting a DVI device to a HDMI input via an adapter, ensure the television's HDMI port is accompanied by its own Left and Right audio inputs. Apart from HDMI, a new television should feature the usual suspects; composite, component, s-video and maybe SCART. Most flat panels also feature a VGA monitor input for connecting to a computer.
Look for inputs on the sides or front of the television, as well as the rear, if you'll be regularly plugging and unplugging devices such as video cameras and games consoles. If the television has a digital tuner, it should also have digital audio outputs (coax and/or optical) for connecting to a surround sound amplifier.
USB and Digital Photo Card Reader
USB ports and flash memory card readers are recent additions to new televisions, allowing you to run digital photo slide shows on your television rather than your computer. Some televisions will also let you play music and video files from a USB stick or memory card.
Ethernet
A growing number of televisions feature Ethernet ports, allowing you to connect your television to your home network and the internet. They use formats such as DLNA (Digital Living Network Alliance) to let you stream audio, video and images from computers and even games consoles such as the PlayStation 3. Some televisions with Ethernet also let you access online video content such as YouTube.
Comparison Net enables an "apples with apples" comparison of TVs. First step is to narrow your search to a short list by filltering all our tvs by brand, price range or features that are important to you.
For example, find all 42 inch high definition screen tvs; or find all LCD tvs with RRP between $2,000 to $3,000; or find all Pioneer Plasma tvs.
You can create a shortlist of the TV models you are interested in, then look for local retailers and deals near you. Confused about some of the terms? Find out more in our jargon busting digital TV glossary.
Review what Choice, the Australian Consumers Association have to say about LCD TVs and Plasma TVs.
See other articles on digital TVs here, including a run down on Plasma Versus LCD tvs, HDTV in Australia and how we calculate our energy ratings for TVs. |
