4K or 60FPS: Which is More Important?

Last week, we talked about how the BlackVue DR750S is still a great camera because it offers Full HD recording at 60fps. In fact, the Thinkware U1000 gives users the option to choose between 4K @30fps or 2K @60fps. Many of you might be wondering if 60fps more important than 4K.

Before we dive into the topic, let’s go over a couple of things:

1. 30fps and 60fps are frame rates
2. 4K and Full HD are video resolutions

Frame rate, or FPS, is the speed at which images are shown. You can think of frame rate like film on a reel or even those little flipbooks where a pad of paper had an image on every page. Each drawing on a piece of paper is a frame. When you flip through the pages quickly, you see all the frames blended and appeared to animate and move. This is essentially how video works.

That in mind, a frame rate of 30fps means that in one second, the camera is capturing 30 individual frames and when played back, it plays 30 frames in a second to make a continuous clip. Similarly, there are 60 images in each second of a 60fps video. In other words, you will have extra frames capturing the same incident.

Here’s a video of a simple visual demonstration of why frame rates matter.

The main difference between 30fps and 60fps is the number of frames captured per second. Here’s a breakdown of the two frame rates:

In general, lower frame rates look choppier and higher frame rates look smoother.

A higher FPS does not mean a higher quality video. Remember, when you change the frame rate, you are not changing the file output size. For example, whether you shoot 30fps or 60fps, you can have the same 2K QHD quality output. The difference is simply in the number of frames captured.

But because you have twice the number of frames every second compared to a 30fps video, 60fps will give you smoother video playback, less blurring and stuttering. And by doubling the frames, you are more likely to capture double the underlying data of situations occurring at higher speed, which means you’re more likely to be able to retrieve critical data.

Another benefit, and probably the most important, of 60fps is the ability to slow the video down allowing for smooth slow-motion video playback. Incorporating better slow-mo always makes good visual content especially when you’re capturing something that is too fast for regular viewing, like a racing or drifting event.

You bet! Even though the image will not appear as smooth as 60fps, 4K still has twice the number of pixels than 2K, resulting in much more detailed video footage. The clarity of the 4K image is perfect for recording in Parking Mode, especially in low-light conditions. The 4K resolution ensures a crystal-clear image which can help to identify a suspicious person around your vehicle.

First of all, there is no best frame rate, and different resolutions at different frame rates yield different results. The typical resolution-frame rate combinations found in most high-end dash cams are 4K UHD @30fps or 2K QHD  (or Full HD) @60fps.

Keep in mind that:

• The higher the resolution, the more the pixels, the better the video quality and the larger the file size
• The higher the frame rate, the crisper the video and the larger the file size.

Ultimately, the choice is up to you. Here are some things to consider when making the decision:

If you are using the dash cam footage primarily for capturing vandals or incidents while away (ie. parking mode), then 4K may be better for you. A 4K resolution will give you better contrast and colour range. 4K will also give you the option to zoom in without losing resolution. But most importantly, 4K is better under low illumination then 60fps.

If you have a lot of motion in your video, you will probably want to capture at a higher frame rate as it ensures a higher level of detail for the amount of motion captured. A higher frame rate also allows for more flexibility when editing. For instance, racing is often recorded at a high frame rate so the video can be slowed down to show replays while still maintaining its crispness and clarity. But do keep in mind that 60fps is weaker at low-lit environments, ie. night time. If you recording footage in low-light environments, 30fps will give you better video quality.

Both resolution and frame rate play an important part in the delivery and viewing experience of a video. But while many smartphone and display screens can handle 4K, not all devices support high frame rates. Let’s take a look at several situations.

Sharing and streaming footage on YouTube is extremely popular. While YouTube allows you to upload files in multiple resolutions (ie. 4K, Full HD), they cap the frame rate at 60fps. Perhaps you have a VIOFO dash cam and you have captured footage in 120fps. You can still upload the video on to YouTube, but it will compress it down to 60fps. Remember that video we shared earlier - the video has 120fps, but YouTube can only show max. 60fps. That explains why the difference between the 60 and 120 fps balls is unnoticeable.

Even if it did display at 120fps, there’d be no point. Most screens can’t display that many frames anyways.

Typically, a higher frame rate requires a better graphics card and processing speed, suitable screen resolution, refresh rate, etc. At its most basic level, a display screen works by showing you a series of images, or “frames”. To make a video, the display needs to show a series of frames, one after another. This is called refresh rate. A 60Hz display refreshes its image 60 times a second.

This all becomes important when more people are using their smartphone to view videos while phone manufacturers are touting phones with high refresh rates in their screens. The Google Pixel 4 comes with a 90Hz screen, while the newest Samsung goes up to 120Hz.

For the best viewing experience, refresh rates and frame rates need to work in tandem - if the two are out of sync, things can get pretty ugly pretty quickly. Taking the VIOFO as an example again, viewing a 120fps footage video on a standard 60HZ screen might produce a nasty effect called “screen tearing.” Currently, most laptops, smartphones, and tablet screens have 60HZ refresh rate. Of course, gaming laptops and the latest high-end smartphones can go up to blazing-fast 90Hz and even 120Hz.

To make a home video of your recorded footage files, you’ll need to use a video editor application or software.

The speed of the SD card is another important consideration when recording in high frame rates. There are different speed classes for SD cards, and the speed determines how fast you can write data to your dash cam. When it comes to high frame rates, a UHS 3 rating is ideal but it is more expensive. Another consideration is the V ratings (ie. V60, V90).

And whether you are going 4K or 60fps, you will need to make sure there’s enough storage space on your microSD card. Both higher resolution and higher frame rates require more storage space. We recommend opting for the max. SD card capacity your dash cam can support. Having a backup SD card is also a good idea.

Both resolution and frame rate play an important part in the viewing experience of your dash cam footage video, and choosing resolution vs. frame rate often means choosing between how crisp you want your video to look and whether or not you plan to implement slow motion or motion blur effects and techniques.

Until next time, Safe Driving!