120Hz LCD TV

Two of the latest buzzwords when it comes to LCD TVs are 120Hz and LED backlit. In this HDTV guide we are going to take a look at 120Hz LCD TV technology. I will give you the naked truth and tell you how LCD TV manufacturers are trying to deceive you. Yes, they are trying to deceive you so that you think you need 120Hz and pay more. 120Hz LCD television sets do have advantages, however these advantages are not those you may think of. They also cost more than regular 60Hz LCD TVs so it is a good idea to know if you really need or prefer 120Hz vs 60Hz.

Response Time vs Refresh Rate

If you read through the specs sheet of an LCD TV or LCD monitor, you may find a reference to “response time”. The response time is measured in ms (milliseconds) and represents the minimum time it takes the LCD to physically change the color and brightness of it’s pixels.

Sometimes, people call this “refresh rate” but that’s not correct. The refresh rate is the rate at which the entire picture displayed on the LCD changes. The refresh rate is artificial, it is determined by electronics and is not a physical characteristic. The refresh rate is measured in Hz (Hertz).

The refresh rate of an LCD display depends on the video signal. For example, on a computer you can change the refresh rate from your display settings. If you set it to 60Hz for example, the picture on the screen will be refreshed 60 times per second, the video card sending a new frame/image to the monitor every 1/60 seconds.

What They Want You to Believe

LCD manufacturers want you to think LCDs are superior to plasma TVs and/or eliminate any possible worries you may have that an LCD is not able to display fast moving images sharply. In case you never cared about that, they want you to think that 120Hz is better than 60Hz (regular). Why? Because an 120Hz model, since it incorporates newer technology is more expensive than a regular 60Hz model.

The Truth!

For a long time, LCD displays (in HDTVs and computer monitors alike) have suffered from poor response times compared to other technologies as plasma and CRT. Until not too long ago, many LCD screens had response times higher than 15ms (they were “slow”). Now you can find LCDs with response times as low as 2ms.

I won’t go into technical stuff here, but the idea is, those LCDs with response times over 15ms made moving images look blurry around their edges. So if you played a game, saw an action movie, sports, etc. the image would have looked a bit blurry. Even if you just moved the mouse pointer around you would have been able to see it’s edges looked blurry. This had nothing to do with the refresh rate you had. Even if you would have had 1000Hz refresh rate (that’s an exaggerated figure) the blurring would have still been visible.

So, does that mean LCDs are bad for games, action movies, sports, etc. because they have a blurry image? Not necessarily. If the LCD has a response time of under 10ms the image will look crisp and clear. I personally use a 22″ Dell LCD computer monitor with 5ms response time and it has perfectly crisp image.

What you need to understand is that the refresh rate (e.g. 120Hz) has nothing to do with the sharpness of the picture. The response time (e.g. 5ms) is the one that can make the picture look blurry or crisp.

Advantages and Disadvantages of 120HZ LCD TV

Advantages

A 120Hz LCD TV offers the theoretical advantage that it can display 1080p/24 Blu Ray movies better (without artifacts). As you may have noticed I said “theoretical”. That’s because in theory a 120Hz LCD should be able to display 1080p/24 correctly without artifacts, but in practice not all of them manage to do it nicely. If you’re a fan of 1080p/24 then your only chance is to read reviews that describe how the specific TV you’re interested in performs in 1080p/24 mode. This applies for any HDTV, plasma TVs being susceptible to the same type of problem.

Another advantage, is that the implementation of 120Hz technology on a TV inserts virtual frames in the movie. Basically, the video processing system inside the LCD TV gets two frames from the movie and generates one or more fake frames that puts between the real ones. These fake frames weren’t in the original movie. This whole process produces a very smooth image.

Disadvantages

The disadvantage is exactly the same as the second advantage above. That is, because of those fake frames that are generated to make the image smooth, the movie will not look as it was intended to look originally. Because of this feature movie content ends up looking as video content. Even worse, in some cases the HDTV can do such a poor job that the movie will look “awful”, “bad”, “ugly”, “unnatural”. Those are the exact words used by some to describe what they though of this technology, when watching TVs that did a poor job at implementing 120Hz technology.

I bet you’re lost right now!

Why did I categorized that as both an advantage and a disadvantage? Because it can be an advantage if you prefer the video-like smooth and crisp picture (as long as the TV does a good job at generating those fake frames), or it can be a disadvantage if you’re a purist and fan of the movie look. The good news is, even if you buy a 120Hz LCD TV you can choose in what mode to use it. So it will look witch ever way you prefer.

A Look at the Market and Best LCD HDTV Models

I just wrote this long guide about 120Hz LCD TVs and by now you are either pro, against or indifferent. If you’re against 120Hz or indifferent, maybe you’re thinking to buy a regular LCD TV and save some money. Well, you need to know something first!

Most high-quality LCD TVs are 120Hz. So if you want the best LCD TV you will end up buying a 120Hz model. They are not the best because they are 120Hz, but because all manufacturers stuff their high-end models with latest features. You can find good LCD HDTV models that aren’t 120Hz and are more in the average price or low price range, but the very good and exceptional models are all 120Hz. The idea is, 120Hz doesn’t have much to do with how good a TV is. Look at other more important features and characteristics when trying to decide on a HDTV model.