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Updated: July 1, 2022 What is the refresh rate on a TV, and do you need a 60 Hz or 120 Hz model? Check out this essential guide to the TV refresh rate if you're not sure. One of the many confusing aspects of buying a new TV is understanding the TV manufacturers’ technical specifications. A TV’s refresh rate is a good example. You get told a particular TV has a refresh rate of 120 Hz, 240 Hz or even 480 Hz. Sometimes more! So, which is the best refresh rate for a TV? The bigger number is better right? Well, not as much as you might think. And, in many cases, not at all. In this article, you will learn about the different refresh rates of LED and OLED TVs and get the answers to the most common questions. It is a complex subject, but you won’t need a science degree to understand the essential points. Summary
What Is the Refresh Rate of a TV?The refresh rate of a TV is the number of times per second the picture is ‘redrawn.’ Or, to put it another way, how many images it can show in one second. The quicker a picture is refreshed, the more it should help motion appear smoother to the human eye and have less flicker. This is a good thing. Video Frame Rates vs TV Refresh RatesFirst up, it’s a good idea to understand the difference between the frame rate of a video recording and the refresh rate of your TV. They are two different things but influence each other. As you probably know, video recordings capture live-action by taking a series of still images – or frames. If these single frames are played back quickly – one after the other – you will see this as smooth motion when displayed on a screen. Historically, the frame rate of analog video was based on the frequency of the local power supply. This means that it was different around the world:
To save bandwidth during transmission, analog video was always interlaced. This means that a single frame was divided into two fields containing the image’s odd-numbered lines and even-numbered lines, and the TV screen would display these fields in the correct order when displaying the video. Therefore, in PAL regions, the frequency of interlaced video was 50 Hertz (Hz): 25 frames per second x 2 fields = 50 fields per second In NTSC regions, the frequency of interlaced video was 59.94 Hertz: 29.97 frames per second x 2 fields = 59.94 fields per second *** There is plenty of confusion about the NTSC 29.97 and 59.94 frame rates. Many people just round these up to 30 and 60 frames per second. But this isn’t actually correct because modern HD cameras can record at 29.97 or 30 and 59.94 or 60 frames per second. So, they are actually two different rates. However, you can just think about 30 and 60 Hz to make things easier. *** By the way, Hertz is a standard for describing the frequency of something, i.e., the number of cycles per second, and it can describe the frequency of anything, not just video frame rates. Why Are Movies Filmed at 24 Frames per Second?Content recorded on film is traditionally recorded at 24 frames per second (fps). Although some movies have been shot in higher frame rates, this still holds today. Why is this different from video frame rates? Simply because when movies were first made, this was the lowest frame rate considered suitable for viewing. It was easier (and cheaper) to build and use the hardware to film and display movies. And it looked good enough to the human eye to be realistic. Over time, it hasn’t changed much because people have become used to watching movies at 24 frames per second. It ‘looks like a movie’ at this frame rate – and most viewers prefer it. So that’s what the video refresh rate is. What about the refresh rate of your TV screen? Well, due to the standard video frame rates that we’ve just discussed, televisions were designed with a refresh rate to match the frequency of the video transmissions. So, TVs in PAL regions had a 50 Hz refresh rate, and TVs in NTSC regions had a 60 Hz refresh rate. Now, these frame rates were developed for analog TV systems. Even so, they’ve remained the standard even with the new digital broadcasting systems – ATSC in the US and DVB in Europe. Modern broadcast video standards support a few different frame rates. The most common are:
The frame rate is sometimes added to the end of the TV picture resolution to describe the format:
The higher video frame rate will display smoother motion as there are more frames to capture it – and it is this which determines how smooth the action will appear on your television – not your TV’s refresh rate. The TV is just displaying what has been initially captured on the video. Refresh Rates for Modern Flat Screen TVsYou now know the standard refresh rate of TVs is either 50 Hz or 60 Hz. So, why do you see different TV refresh rates quoted when you buy a new TV? You can see quoted refresh rates of 120 Hz, 240 Hz, 480 Hz and more. To begin with, you should understand that the maximum native refresh rate of a modern flat-screen TV today is 120 Hz. This means it can display 120 images every second. So, the TV you buy will either have a 120 Hz refresh rate – or the older standard of 60 Hz. In Europe, this will more likely be 50 Hz or 100 Hz – although a modern TV in this region will often support 60 and 120 Hz too. So, if you want a TV with the highest native refresh rate – this will currently be 120 Hz – and all TVs will either be 60 or 120 Hz. Any quote you see higher than this is marketing hype designed to make you buy a ‘better’ TV. The bigger number must be better, right? You will learn about these higher refresh rates later. 60 Hz vs 120 Hz TVsSo, is a 120 Hz TV better than a 60 Hz TV? The obvious conclusion is that a TV with a 120 Hz refresh rate will display a smoother image. However, it’s not as simple as that. You also need to consider the frequency of the content displayed on the TV. And, you now know that the frame rate of the content, and the refresh rate of the TV, are two different things. If you take a video recorded at 60p, each frame is repeated twice to display it on a 120 Hz TV: 60 fps x 2 = 120 fps For a 30p video, each frame is repeated 4 times: 30 fps x 4 = 120 fps However, this makes no difference to how smooth the image looks, and there is no increase in detail of the movement. Your 120 Hz TV just shows you the same frames you would see on a 60 Hz TV. Also, when you input a 60 Hz video, some 120 Hz TVs will just switch to a 60 Hz refresh rate. So, again, no difference to a standard 60 Hz TV. So, does this mean that there is no point in buying a 120 Hz TV? No, but it does mean the benefits will not be as great as you think. The main benefits of a 120 Hz TV are:
So, while there are some benefits of a 120 Hz TV, you may not find many of them that useful in your day-to-day viewing. Now, if you are buying a new TV, you may not have a choice what you get anyway. The refresh rate on a 4K TV will often be 120 Hz – even though some will claim to have more – and cheaper models may only be 60 Hz. The refresh rates of the featured models are listed in the best OLED and LED flat-screen TVs in 2022. So, how do you explain the higher refresh rates of 240 Hz and above? 240 Hz & 480 Hz Refresh Rate TVsYou might see a TV advertised with a refresh rate of 240 Hz. Good, huh? No, because it isn’t. A refresh rate of 480 Hz? Wow, that sounds great! Except, it isn’t really. As mentioned previously, there are currently only two actual refresh rates for TVs in the US – 60 Hz and 120 Hz. These are native refresh rates, i.e., the rate at which the TV can actually redraw the screen. Anything else you see is marketing smoke and mirrors released by the manufacturer to make their TV more appealing. These ‘increased’ refresh rates are just inflated numbers that can only be realized by the TV processing the picture. There are a few different ways TV manufacturers try to achieve smoother motion. The most common are motion interpolation and black frame insertion/backlight scanning. It is these processing techniques that are used to justify claims of higher refresh rates. Each manufacturer has its own name for this processing. Some examples are:
Each processing mode is used to claim a refresh rate higher than the actual figure for the TV, making it very difficult to compare like-with-like. Samsung Motion Rate vs Refresh RateFor example, with Samsung, a motion rate of 120 for a 4K TV will have a native refresh rate of 60 Hz. A 4K Samsung TV with a motion rate of 240 will have a native refresh rate of 120 Hz. As you can see, unless you are aware of this, it can be challenging to understand the difference between the motion rate vs. the refresh rate. Unless you like the picture processing that TVs do, you don’t need to worry about the motion rate (or whatever the brand calls it). You just need to find out the native refresh rate – which you should find in the specifications on the manufacturer’s website – or in a technical review of that model. What Is Motion Interpolation?The idea behind motion interpolation is to increase the frame rate of a video source by adding extra frames. Frames that don’t exist in the actual recording. Therefore, to make a 60 Hz video playback at 120 Hz (or more), you can enable motion interpolation in the display menu of your TV. Each manufacturer will call this something different, but the idea is the same. Motion interpolation creates extra frames by making an educated guess of the movement between two frames – effectively taking two consecutive frames and creating an extra one between. So, if the frames of a 60 Hz video go from this to this: Then the motion interpolation will add an extra frame in the middle. The result is the motion will look smoother because there is less of a jump from one frame to the next: The trick to making this work effectively is how well the interpolation algorithm performs the task. While this can work well for some fast-moving images like sports, many people don’t like it. It can create an image that looks very unnatural – especially if used with movies – and this look is often called the ‘soap opera effect.’ Motion interpolation is also not recommended for gaming as the required processing can introduce lag. So, it is OK to watch TV shows, but it makes gaming difficult. If you are unsure, just switch it on in your TV’s menu and see what it looks like. You can always turn it off again! Backlight Scanning and Black-Frame InsertionThese techniques are used on some TVs to improve motion… and allow the manufacturer to claim a higher refresh rate. They are not directly connected to the refresh rate of a TV, but they can be more effective on a TV with a higher 120 Hz refresh rate. Backlight scanning and black-frame insertion are essentially the same processes, and they are called different things by some manufacturers. The idea is that by turning the screen black in between each video frame, the eye is tricked into seeing smoother motion. This works because motion blur is caused in part by the pixels of the TV screen not switching color quickly enough. With TVs, they use a process called sample and hold, resulting in the pixels holding on to their color for a fixed period – and the human eye can see this as a blurring of the image in fast-moving pictures. One solution to this problem is to make the screen black in-between frames, making the color transition of the pixels much sharper and cleaner. Anyway, the details on how it works are less important. You just need to know that some people think it can be pretty effective – and others can’t stand it. These features are usually enabled and disabled in the menu settings for the TV, so try it out and see what you think. What Is TV Motion Blur?Motion blur has been mentioned a couple of times already, so it’s a good idea to explain what this is. It’s an essential issue related to TV refresh rates because people get confused between television refresh rates and the motion blur they see on screen. They assume that a high refresh rate will remove motion blur, which can help, but it’s not the solution. Don’t forget that the source material’s frame rate is significant in seeing smooth motion. Progressive video recorded at 60 fps will look smoother than 30 fps video because it captures more detail in the movement. But motion blur is something different. Motion blur on a TV occurs when the image appears blurry with quick movement on the screen and is especially noticeable with sports content. Motion blur on a TV screenIt is a misunderstood issue because the motion blur that you see can be caused by several different factors:
All of these can contribute to what people see as motion blur, and as you can see, none of these are directly caused by a low refresh rate. In a modern TV panel, there are a couple of ways to try and fix the effect of motion blur – motion interpolation and backlight scanning – which have been discussed further up the page. While a higher refresh rate can help make these techniques more effective, it is just a tiny part of reducing TV motion blur. While motion blur on a TV can be very annoying, some people are more sensitive to it than others. ConclusionSo, what have you learned from all this technical mumbo jumbo? Unfortunately, you have read a lot of words saying that the refresh rate of your TV isn’t that important. Maybe that should have been said in the first place and saved a lot of time – although it wouldn’t have been as much fun! The main takeaway is that the quoted refresh rate of a TV should be taken with a pinch of salt. If it says anything higher than 120 Hz, then it isn’t the real native refresh rate – and even with the correct numbers, there aren’t too many instances where a higher refresh rate will significantly affect your daily use. If you like delving into the menu and changing a few settings, you may improve performance in some circumstances. However, many people don’t like the look of the processing modes you can enable, so they don’t use them. In many cases, you will buy a TV based on your budget, and the more expensive models will likely be 120 Hz – and the cheaper ones will be 60 Hz. Simple. Just don’t get too hung up on the higher numbers. Frequently Asked QuestionsIf you want some quick and simple answers to common questions, here are a few frequently asked questions about TV refresh rates. What Is a Good Refresh Rate on a 4K TV?There are only two native refresh rates for 4K TVs – 60 Hz and 120 Hz. Any number you see quoted above this isn’t the TV’s real refresh rate – it’s just created by image processing techniques. Most people will see little difference between 60 and 120 Hz refresh rates, so it’s not something to worry about too much. Is 120 Hz Better Than 60 Hz for a TV?A 120 Hz TV has some benefits over a 60 Hz TV, but most people will not notice the difference. A 120 Hz TV will display 120 Hz content as intended – but there’s not much of this. It may also show 24 Hz movies with smoother motion and reduce motion blur for some people. Is 60 Hz or 120 Hz Noticeable?The difference in performance between 60 Hz and 120 Hz is relatively small. In some circumstances, viewers may notice smoother motion on the screen, but it will make little difference for most people. You will only get the full benefit of a 120 Hz TV if you have content that is created at this frequency. What Is a Normal TV Refresh Rate?Modern TVs have a native refresh rate of either 60 Hz or 120 Hz. How to Check Your TV’s Refresh Rate?It can be challenging to know the native refresh rate of your TV because many manufacturers quote elevated numbers. The native refresh rate can only be 60 or 120 Hz. If a manufacturer quotes a ‘motion rate,’ the native refresh rate is often half that number, although this varies. Another way is to check quality reviews for that TV, which should quote the actual number. Is 120 Hz TV Worth It for Gaming?If you have a game created at 120 Hz and can use the latest HDMI 2.1 specification on all your hardware, you will benefit from higher refresh rates. Otherwise, it will unlikely make much difference. Can a 60 Hz TV Run 120 fps?No, a 60 Hz TV can only display 60 frames per second. A 60 Hz TV can use image processing to interpolate 30 fps video up to 60 fps – but the TV cannot show more than 60 frames every second. Does Refresh Rate Matter on an LED TV?In most cases, the refresh rate has little effect on the performance of a TV. On TVs with a high refresh rate, the picture may appear smoother to some people – with less motion blur. But the main limitation is the frame rate of the content, which is unlikely to be created at higher refresh rates, so your TV’s refresh rate will make little difference. Pin Me!About Home Cinema GuidePaul started the Home Cinema Guide to help less-experienced users get the most out of today's audio-visual technology. He has worked as a sound, lighting and audio-visual engineer for around 20 years. At home, he has spent more time than is probably healthy installing, configuring, testing, de-rigging, fixing, tweaking, re-installing again (and sometimes using) various pieces of hi-fi and home cinema equipment. You can find out more here. Image Credit: iStock.com/isitsharp Home Cinema Guide may get a commission if you buy from a link marked with * on this page: about ads What is a good motion rate for a 4K TV?What is this? The refresh rate on a 4K TV will often be 120 Hz – even though some will claim to have more – and cheaper models may only be 60 Hz. The refresh rates of the featured models are listed in the best OLED and LED flat-screen TVs in 2022.
Is 60Hz or 120 motion rate better?In theory, a higher refresh rate should equal a better quality picture because it cuts down on blurriness. A 120Hz display decreases the appearance of "film judder" or blurring that might be noticeable to some on a 60Hz screen. Improvements beyond a 120Hz refresh rate are unnoticeable.
Is motion rate 120 the same as 120Hz?No. Clear Motion Rate is a term used by Samsung to encapsulate the combination of a screen refresh rate with software image processing techniques. Clear Motion Rate is often measured as twice the value of the true refresh rate. That means a 60Hz refresh rate TV will have a 120Hz Clear Motion Rate.
Is a higher motion rate better on a TV?A TV with a higher rate offers a smoother watching experience because it can display more frames per second than a TV with lower rates.
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