Monday, 16 July 2012

LED LCD vs plasma vs LCD

Debating on what HDTV technology to buy? Debate no longer. OK, not too much longer.

In this television technology trifecta, which comes out on top? The subject of countless debates and diatribes, the better question is: which works best? Or more precisely, which works best for you?
When you cut through the hype and the fanboys, each tech has different benefits and costs. So to help you figure out which TV is right for your house, let's take a look at each one.
First, a BIG disclaimer: any article of this type is, by necessity, going to contain a lot of generalizations. In most of the categories below, there are likely one or two exceptions to each rule. It's great to find an outlier, but that's just what it is, an outlier. The "average" product featuring these technologies is going to perform as listed.
Second, some terminology. 
Plasma TVs, made by Panasonic, Samsung, and LG, range in size from 42 inches to roughly 65 inches. There are some larger models (notably Panasonic's 150-inch), but for most people, they max out at 65 inches.
LCD TVs range in size from a couple of inches, to 90 inches, and everywhere in-between. They're made by everybody. All "LED TVs" are actually LCD TVs, they just use LEDs as their light source, instead of the traditional CCFLs. As they tend to perform a little differently, and are marketed way differently, we'll address them separately. LED models also tend to be the higher-end models from a particular company, so often their performance advantage can have to do with this more than the inherent technology.
You might ask yourself, at this point, why only three companies for plasma? When electronics companies started building their manufacturing plants for TVs, they faced a choice: make big "cheap" flat panels that can't go much below 42-inches (plasma), or build a more expensive factory that can make a wide variety of sizes, even though the bigger sizes will be more expensive (LCD). As production has increased, the larger LCD sizes have become more price competitive, so that distinction has disappeared. As such, you don't see a lot of companies investing in new plasma TV manufacturing. Not when an LCD factory can make everything from cell phone screens to 90-inch HDTVs (an over simplification, but you get the point).
Light output (brightness)
Winner: LED LCD
Loser: Plasma
Runner-Up: CCFL LCD
Without question, LED LCDs are the brightest TVs you can buy. Some models are capable of well over 100 footlamberts. To put that in perspective, in a movie theater you're lucky if you get 5. CCFL LCDs are a close second.
Plasmas just aren't that bright. It's all relative, though, as plasmas are still likely way brighter than old-school CRT tube TVs. So plasmas aren't "dim," but they aren't nearly as bright as LCDs.
The question is, do you need that light output? In a dark room, 100 footlamberts will be searingly bright. In a bright room (daytime/sunlight) a plasma might be hard to see.
Another aspect to consider is any antireflective or antiglare material on each screen. A plasma with a really good antireflective coating may be better to watch with room lighting than a glossy-screen LCD with no such coating (and vice versa).
Black level
Winner: Plasma
Runner-up: LED LCD
This is getting a lot closer, but plasmas still offer the best black levels. Yes, LED LCDs can sometimes have an absolute black (by turning off their LEDs), but when you're watching a movie, plasmas are going to seem darker. This relates to contrast ratio...
Contrast ratio
Winner: Plasma
Runner-up: LED LCD
Contrast ratio, or the ratio between the darkest part of the image and the brightest, is one of the most important factors in overall picture quality. A display with a high contrast ratio is going to seem more realistic, and have more virtual "depth." I highly recommend reading this article:Contrast ratio (or how every TV manufacturer lies to you).
There is one exception. The new Elite LED LCD (made by Sharp) has an advanced local dimming backlight, which gives it a plasma-like contrast ratio... for a price. A big price. One good LED LCD doesn't make them all good, nor does it herald a new generation of better LED LCDs. The Sharp/Elite doesn't do anything new. It's a local dimming LED LCD. We've actually seen fewer and fewer of this types of displays for the reason this TV makes quite obvious: price. Local dimming LED LCDs are more expensive than edge-lit models (and typically more expensive than plasmas, at the same size), and these days, expensive TVs aren't big sellers. 
Do a few other local dimming models come close to the better plasmas (or exceed the lesser ones)? Yes, but again these are the exceptions, not the rule.
There are some technologies coming down the pike that may offer even better contrast ratios. One of the most exciting is OLED. I'm really excited about OLED. It promises to be the best of all words: the best picture quality going, ultra-efficient, and incredibly thin. To learn more about this upcoming TV technology, check out What is OLED TV?
So, on average, plasmas have a better contrast ratio (with notable exception noted). If you're curious why they don't look like it when you see them in a store, check out Why do plasma TVs look washed out in the store?
Viewing angle
Winner: Plasma
Runner-up: IPS LCD (see text)
How big is your room? Do you or loved ones sit off to the side, viewing the TV at an angle? If so, it's important to note that LCDs of both flavors lose picture quality when viewed "off axis," as in not directly in front of the screen.
Small room, small couch, mother-in-law Barcalounger off to the side? Don't worry about it.
Somewhere in the middle are in-plane switching LCDs, which offer a better viewing angle at the expense of overall contrast ratio and black level. Check out my article Myths, Marketing, and Misdirection for more info.
Energy consumption
Winner: LED LCD
Loser: Plasma
Runner-up: CCFL LCD
No question, LED LCDs have the lowest energy consumption, especially when you turn down the backlight. Prius drivers, this is the TV for you. CCFL LCDs are a close second, with the same addendum.
Plasmas, especially when you turn up the contrast control (which you need to for them to look their best), just aren't as energy efficient. They are, however, far better than they were a few years ago.
If you want to go green, get an LED LCD. As I mentioned in the Myths article, though, it won't save you money. Because LED LCDs are more expensive than other TVs, it will take you years to make up that difference in energy savings (if ever). We're talking a few dollars difference in a year here. Check out HDGuru's article HDTV energy guide labels explained.

Winner: CCFL LCD
Loser: LED LCD
Runner-up: Plasma
Because they tend to be at the lower-end of a company's TV offerings, CCFL LCDs are the cheapest TVs you can buy.
As mentioned earlier, LEDs are the technology behind many company's high-end offerings.
The cheapest "doorbuster" TVs will almost always be CCFL TVs. Plasmas tend to have the best size/price ratio.

Multiple studies by a variety of sources have found flat panel TVs to be extremely reliable. Internet forums are always populated by the angry, so invariably you're going to read more "well mine broke!" posts than "I've had mine for 5 years and it's great."
Gotcha! All TVs can burn in. It's unlike you'll abuse them enough for this to happen (think airport arrival/departure displays). Plasmas can have image persistence, which has the outward appearance of burn-in, but isn't permanent. For more on this, check out my article Is plasma burn-in a problem?
The short version? You're going to notice image persistence long before it will become a problem.
Winner: Plasma
Uniformity, or a consistent brightness to the image, doesn't bother me a lot. It bugs David a bunch, though. Check out my article Is LCD and LED LCD HDTV uniformity a problem?
Plasma can have issues in this regard as well, though they're far less frequent or noticeable. Edge-lit LED LCDs are the worst offenders, though cheap CCFL LCDs have their own issues. In many cases, the uniformity will vary per sample. So your TV might be fine, but your brother-in-law hates the one he bought of the same model.
And the winner is...
If you want to count wins and losses from the list above, have at it. The thing is, these items don't have equal weight. That's the point. For one person, absolute light output is absolute, for another, black level is above all else. These two performance aspects are, for now, mutually exclusive.
So don't listen to those who say, "well, its brightest, it's best" or "LCD's black level is terrible, so they blow." Reading through this list I'm positive you've mentally weighted certain factors above others, even if you didn't notice it at first. Go with your gut. If you watch a lot of TV during the day, or have a room with lots of windows, LED LCD is probably best. If you watch at night, and want the TV to disappear into the background, plasma is probably best.
Want to know the best part? The dirty little secret of the TV world? If you're buying a name-brand TV, its picture quality is going to be really, really good. You are seriously picking from good, gooder, and goodly goodest here. Compared with flat panel TVs from just a few years ago, new HDTVs are thinner, brighter, bigger, better-performing, and cheaper than ever before. So have at it. Your new TV is going to be awesome for years to come.