Why you want a 120Hz TV even if you’re not a gamer
TVs with a refresh rate of 120 Hz have become popular thanks to the latest consoles that offer a mode of 120 frames per second in certain games. However, 120Hz TVs also solve a fundamental problem that 60Hz has with frame rates of cinematic content.
What does 120Hz do?
If you’re not entirely clear about what a refresh rate is, check out our monitor refresh rate tutorial for a detailed and simple explanation. If you’re in a rush, the short answer is that refresh rate is a measure of how many times a screen can completely redraw what’s on the screen in a second. So a 60Hz screen can complete 60 full refreshes in one second and a 120Hz screen can double that number.
However, don’t be fooled by marketing terms. If you’re buying a TV, make sure the TV’s native refresh rate is 120Hz. Some 60Hz TVs advertise with a higher number under names like “smooth motion” or “motion plus”. These TVs cannot accept and display a true 120Hz video feed. Instead, they use various tricks to make movements on the screen appear smoother. This is the dreaded “soap opera effect” that people complain about when it’s enabled by default out of the box.
Frames vs Refresh Rate
The refresh rate determines the maximum number of frames the TV can display in a second. A frame is a single photo in a series of photos that make up a video. The number of unique snapshots a camera takes while filming or a game system takes while playing is known as the frame rate.
If the frame rate matches the screen’s refresh rate perfectly, you’ll get the ideal image, but most of the time this isn’t the case. The most common frame rate for cinematic movies is 24 frames per second.
Likewise, a lot of TV content is recorded at 24 or 30 frames per second. Some weird experiments, like The Hobbit trilogy, were shot at 48 frames per second. Content shot at 60 frames per second is becoming more common, but you’ll likely find it on platforms like YouTube, especially in action sports content or other videos with fast-moving subjects.
This is where we hit a snag with the near-universal 60Hz television set. Most of the content you watch on your 60Hz TV is not 60 frames per second. That sounds like a problem, right?
For content with a speed of 30 frames per second, this is not a problem. Each frame is simply displayed twice as 30 is evenly divided into 60. But 60 divided by 24 is 2.5! So how does your TV deal with this problem?
The pulldown problem
The most common “solution” to the 24 frames per second problem is known as a 3:2 pulldown. Each frame of the 24 frames per second signal is displayed for 3 and 2 screen refreshes in an alternating pattern. This prevents a frame change midway through the odd frame, which would act as screen tearing, but it introduces uneven frame pacing. In other words, frames are not displayed at the same intervals.
To the eye this presents as vibrations. Judder is most apparent in panning shots, where the camera movement has a herky-jerky quality that is quite off-putting.
Some TVs have a flicker remover, which changes the refresh rate to an exact multiple of 24, such as 48 Hz or 72 Hz. If you already have a 60Hz TV with a vibration removal feature you’re good to go, but if not, it makes sense to turn your next TV into a 120Hz model
120 is the magic number
If you have a 120Hz TV, the 24, 30 and 60 frames per second content will all be spread evenly across the refresh rate. That means you get a perfect frame rate and see every frame in the content. If you’re serious about cinematic content released at 24 frames per second, a 120Hz TV has a place in your home entertainment system, even if you never plan on playing video games on it.