60Hz vs 120Hz LCD TV
When choosing a new LCD TV to buy, there is a new feature that people may be attracted to; it’s the 120Hz refresh rate. But what do you really get with 120Hz that you do not get from the typical 60Hz refresh rate. The main difference between 120Hz and 60Hz refresh rate is how fast they change the display on the screen. 120Hz refreshes the screen 120 times every second, twice the 60 times per second for 60Hz.
The speed of changing the image on the screen is quite beneficial if you have fast moving scenes like sports and in some movies. With the slower 60Hz refresh rate, the scene may appear jerky or blurry because the change on the screen is too large for the brain to string along as a single motion. With the additional frames achieved by 120Hz, the changes with every frame are not too big and the brain is still able to meld the images together as a moving picture.
Another difference between 60Hz and 120Hz LCD TV is how they display movies that are shot at 24fps, typical for most movies shot on film. With 60Hz LCD TV, 3:2 pulldown needs to be implemented to convert the frame rate to 60Hz. 3:2 pulldown duplicates the frames by 3 and by 2 alternately. So 12 of the 24 frames are shown three times while the other 12 are shown twice. This results in (3×12) + (2×12) or 60 frames, to match the 60Hz LCD TV. This technique is not perfect and it may produce artifacts on the screen because of the inconsistent rate of displaying the images on the screen. With 120Hz, 3:2 pulldown is not necessary because each frame is just shown five times (5×24) for a total of 120 frames per second, thus matching the 120Hz refresh rate of the LCD TV. This is also true for other frame rates like 30fps (30×4) and even 60fps (60×2).
120Hz LCD TVs are nice to have since they give you better pictures in certain situations. But if your budget does not permit it, having a 60Hz LCD TV is not that bad.
Summary:
- 120Hz LCD TV refreshes twice as fast as 60Hz LCD TV
- 120Hz LCD TV is better with fast moving scenes than 60HZ LCD TV
- 120Hz LCD TV does not utilize 3:2 pulldown while 60Hz LCD TV does