4K, UltraHD, HDTV ... what are they and what are the differences between each one


Before, when talking about televisions, we would hear terms like high definition , Full HD or 1080p to refer to the resolution of digital images . Now other concepts such as 4K , ultra high definition, UltraHD or UHDTV are more and more frequent . 4K resolution also appears in reference to commercial movie theaters with digital projectors. Apart from 4K televisions , there are 4K projectors and other compatible home products on the market, such as A / V receivers , home theater systems all in one, digital cameras and camcorders.

The truth is that 4K began its journey in theaters and from there it went to the home with the first consumer 4K projectors last year. Also in 2012, the first 4K ultra-high definition televisions ( UHDTV ) went on sale , capable of displaying images with four times the resolution of Full HD televisions. What does it all mean? What resolution does it translate into? Let's start with Full HD or, what is the same, HDTV . HDTV or Full HD images have 1,920 horizontal pixels by 1,080 vertical pixels, which translates to almost 2.1 megapixels in total for a 16: 9 aspect ratio.


The Full HD TV represent a major advance over images of standard resolution (SDTV), which are 720 by 576 pixels in 4: 3 format for emissions in the PAL system used in Spain and most of Europe. In contrast, when we compare a 4K UHD or ultra-high definition television , Full HD screens have four times less resolution: UHD (UltraHD) offers 8.3 megapixel images ( 3,840 by 2,160 pixels) with an aspect ratio of 1, 78: 1, compared to 2.1 megapixels (1,920 by 1,080 pixels) with a 16: 9 aspect of Full HD.

However, when 4K refers to digital movie theaters ( 4K cinematic ), the native resolution is 7 percent higher than UHD for 4K TVs; specifically, 4,096 by 2,160 pixels (8.8 megapixels) for a 1.90: 1 aspect. Around the world, there are already about 20,000 cinemas offering 4K resolution.

Movie studios have realized the alluring opportunities of 4K . Films released on Blu-ray mastered in 4K are already on the market , a catalog that is growing rapidly. There are classic titles like "Straw Dogs" or "Taxi Driver" to novelties like "Django Unchained." Similarly, European public television networks have been conducting tests for some time. For example, last February of this year 2013, RTVE participated in the first 4K video production experience recorded in our country. And since last year, YouTube allows watching 4K videos in streamingAlthough they are a resolution of 4,096 by 3,072 pixels and a 4: 3 aspect.