4K CCTV: What is 4K?

What is 4K?

In recent years the term 4K has been thrown around more and more but what does it actually mean?

Firstly we need to look at how the image is made up. A simple image is created with square-like dots, known as pixels. The resolution represents the size and aspect ratio. 4K resolution is made up of approximately 4 times as many pixels (horizontal resolution of 4096 pixels) when compared to a 1080p aka Full HD image.

This is the resolution proposed by the Digital Cinema Initiatives. Since the aspect ratio of the movie is different, the exact shape of the rectangular screen determines the aspect ratio of the movie, so it’s vertical resolution is not specified.

Therefore, strictly speaking, "4K" is not Ultra HD, and the resolution of Ultra HD is 3840×2160. The pixel difference between the two is only 13%, and basically no difference is seen. Most people prefer the name "4K" to indicate Ultra HD.

The image below shows the differences between the main resolution formats.

Why would I want a 4K CCTV system?

4K CCTV will provide a clearer image than a 2mp (megapixel), 3mp or 4mp camera. 4K cameras are 8mp which will allow you to digitally zoom much further into your image before it begins to distort.

Is a 4K system not too expensive for me?

As the 4K technology has become more commonplace the prices for 4K CCTV have dramatically decreased. To get the best out of 4K CCTV you would need to view the cameras on a 4K TV and these are starting to become the norm these days. Also when 4K CCTV first burst onto the scene it was very storage intensive and needed a lot of space but advances in the H265 recording format have drastically reduced the amount of hard drive space recording will take up.