When to choose a Plasma television, and why. Plus we bust some myths about Plasma TVs.
An aricle from the experts at AVForums.
Since tube (CRT) technology has been superseded by flat screen TVs, there are really only two TV technologies available right now, and these are Plasma and LCD. They are two competing technologies, each with their advantages and disadvantages. Note that LED TVs are LCD TVs with LED back or edge lighting.
Both Plasma and LCD technologies manage to produce high quality images when correctly manufactured and set up within the home.
Plasma is a self-emitting technology meaning it creates its own light, very much like the old CRT TVs. This helps the technology produce realistic blacks in the picture. LCD technology uses a backlight which is usually a strip of lights (LED lights in 'LED TVs') to the side or back of the screen. Because this light shines through the LCD panel (which opens pixels to allow light through) it is more difficult for LCDs to produce a deep black on screen at the same time as showing shadow detail. This approach also means that the amount of light shown across the LCD screen is not uniform and can show pools (or cones) of light spill on screen. Plasma on the other hand, being self-illuminating, can achieve far more consistent light uniformity. Because of the image strong points, Plasma TVs have found a large fan base with movie enthusiasts for displaying pictures that are accurate and natural.
When to choose a Plasma TV?
Choose Plasma when picture quality is paramount. Plasmas in almost all cases are able to produce images that have rich deep blacks with good shadow detail, excellent motion resolution and accurate colours - so are often the first choice for the discerning viewer. Choose Plasma when you want a screen larger than 40 inches. Plasma does not come in sizes smaller than this, so in those cases where you want a smaller screen your only choice at this time is LCD. Plasma is available in sizes up to 152 inches, with the most popular sizes being 42 and 50 inches. If you have a room where you can control the lighting, or amount of light that comes into the room then Plasma technology is for you. Because of how the technology works it is much better suited than LCD to watching movies in dimmed conditions. An LCD in the same conditions is likely to have lighter blacks and worse screen uniformity because it uses a backlight. Since Plasmas are made from glass (two sheets of glass bonded together with a vacuum containing gas), they may not work as well as LCD in bright conditions. This has been an issue in the past with light hitting a Plasma screen and washing the image out. Most new Plasma models are fitted with a filter that rejects ambient light and stops the image from being washed out. However, Plasma is not as bright as LCD and in some cases where you want a screen in a bright room such as a conservatory or very open room, you may find that LCD will give you a more consistent picture. It has to be noted that a TV in such a room will never give you the best possible image quality and will be a compromise. The amount of light in the room where you use your TV will influence how good the picture is. Choose Plasma when you need a wide viewing angle. When you have people sitting further off to the side of the TV, Plasma is preferable since its picture does not degrade. An LCD TV's picture, on the other hand, looks worse the further to the side of the TV (or 'off axis') you sit. Choose Plasma where you are going to watch a lot of sports or fast moving images. Amongst Plasma's strengths is motion resolution where images do not smear or blur as soon as the action on screen speeds up. This also means that, unlike LCD, technically Plasma does not need motion interpolation systems to help produce natural motion. Typical Plasma models will resolve up to 1080 lines of information compared to an average of 300-400 lines on an LCD or LED LCD TV. (Note there are some exceptions to this with certain individual models). The vast majority of Plasma screens also have low input lag which means that those who like to play video games on their TVs will benefit in most cases with Plasma over LCD.
Common misconceptions about Plasma 're-gassing', lifespan, screen burn and more.
Plasmas do use gas, but it never escapes and they never require 're-gassing'. Anyone telling you that Plasmas need re-gassing is spreading an urban myth. This is still a favourite tactic with many sales staff and is completely wrong. Both Plasmas and LCDs have a good lifespan. Some manufacturers quote lifespans of 100,000 hours, which at 8 hours per day is 34 years. In other words you will probably replace your TV before it gets close to half its lifespan. Screen burn is another term used by sales staff who may try to push a customer towards LCD (or LED) instead of Plasma. Screen burn is more or less a thing of the past and will only ever happen if the Plasma TV is abused, i.e. used in dynamic mode with contrast up full and left on a TV channel with bright logos for a few days. Most modern Plasma screens can stand up to hours of gaming or news channel viewing if done so with appropriate picture settings and for normal periods of time. Image retention is usually mistaken for screen burn but is a natural by-product of Plasma technology and is not permanent. It is usually seen if the TV is used for a few hours of gaming or news channel viewing where there are static images on screen. After changing from gaming or the news channel, there are graphics or text boxes still seen as a faint 'ghost' over the picture. Image retention usually disappears within a few minutes. The severity of the problem does vary from manufacturer to manufacturer with the effect disappearing from most modern screens within a few minutes. The vast majority of people never notice image retention. Plasma TVs do not produce a softer image than LCD TVs. Both will show HD images with the same clarity. Any differences come down to other factors like added sharpness by the video processing of the TV. Although several TV manufacturers like Sony, Hitachi, Philips and Toshiba have abandoned Plasma technology, others like Panasonic, Samsung and LG continue to develop it. Plasma is by no means a dying technology. Many users and professionals still regard Plasma as the technology for critical viewing. Plasma TVs are not particularly power hungry if they are set up correctly. They do generally use more power than LCDs, but because the technology is self-illuminating it means that power function is never close to the maximum rated output for any length of time, whereas LCD stays at the same level when switched on (as the backlight is usually constant). Correct calibration can reduce power consumption by up to 50% in some cases (THX research, 2009).
Plasma TV prices
Plasma has often been seen as a premium technology because it is available in screen sizes over 40 inches and not in smaller sizes. It is also more expensive to produce and manufacture and has to be built in large numbers. However, as production techniques from manufacturers like Panasonic have improved, this has allowed Plasma to be more affordable to the mass market. With the introduction of LED Backlit LCD TVs which command a price premium for being slim, Plasma has become even more cost effective in performance and price terms. A quality Plasma screen these days costs the same or even less than a competing LED LCD model.
Black levels on Plasma TVs
Black levels are considered by many to be a strong point of any TV. In all cases this must also mean that shadow detail (details just above absolute black) must also be seen. To obtain a black that doesn't look grey on screen, some TVs such as LCDs and some low end Plasmas can show blacks that appear black, but which cover over the shadow detail (an effect referred to as clipping). Some LCD and LED LCDs also add in a technique called global dimming where the backlight is switched off or dimmed down to try and create black. Global dimming affects the whole screen. Plasma, because it is self-illuminating, can in most cases (when set up correctly) achieve a black level which looks natural and shows the correct amount of shadow detail. It also means that mixed scenes (an image with very dark areas along with some bright areas) look more natural on a Plasma screen than on an LCD.
Better motion on Plasma TVs
Plasma technology handles motion very well and it is a plus point of the technology as it was designed for showing moving images. There is usually no need to add motion processing to Plasma screens like there is for LCD models. It is true that some recent LCD and LCD LED TVs have improved their motion response with fast moving images, but in this area Plasma is usually still better.
Best settings for your Plasma TV
Copying settings from owners of a similar Plasma TV is a futile exercise as each screen (even the same model) varies considerably. So one set of settings that may work for one owner, will look completely different to another. However there have been recent improvements to the picture presets these days, with some that aim to try and get as close as possible to the industry standards. The industry standards are the settings that film makers and TV producers use when making their programs and movies for home viewing. This means that white and all the colours match the movies you watch on your TV. THX certified Plasma TVs have at least one preset in the picture menus which set the colour gamut and white colour as correct as possible so you can watch all your TV and film material on your TV with (close to) correct colours and white point. All you have to do is make sure the brightness and contrast settings are set for your room using the test patterns found on some DVDs and Blu-rays. THX picture mode is not just for using with THX certified DVDs as suggested in some manufacturers' manuals. It is designed to be used with everything you watch on TV.
Some Plasmas also have a picture wizard feature that will walk users through a basic calibration on the TV.
To get the best from your TV we would always recommend a professional calibration. This is especially true if you have gone for one of the more expensive screens and you want to get the very best out of your investment.
If you want a natural image with accurate colour, good black levels and excellent motion resolution, and your viewing conditions are appropriate, go for Plasma.
As always, there is no such thing as a perfect TV and what will suit you is determined by your viewing environment, budget and the type of material you want to view on your TV. We would always recommend that you do some research and demo the models you think will suit your needs before you spend your hard earned money.