Difference between HD, Full HD, Ultra HD, 4K, 8K and other screen resolutions
Theresolutionrefers to the number of pixels that a screen is capable of offering and it is measured by multiplying the pixels across the width and height of it. As a general rule, the higher the number of pixels, the higher the resolution.
In the field of digital television, specifically high definition television, the acronym HD refer to the resolution of a screen that has 1280 x 720 pixels, also known as 720p.
Among the most popular screen resolutions are those with a resolution Full HD or from 1920 x 1080 pixels. This resolution is also called 1080p.
The denomination Ultra hd describes those screens with a resolution of 3840 x 2160 pixels. These screens are usually promoted with the description "4K", for having almost 4000 pixels across it, despite the fact that this name is not the most appropriate.
The resolution 4K, known as DCI 4K, is a format used originally and mainly in film production and in movie screens. These displays have a resolution of 4096 x 2160 pixels.
Regarding the resolution
8K, it has 7680 x 4320 pixels. This resolution is also known as Full Ultra HD and it is the latest generation of high definition displays to hit the market.Among the factors that influence the resolution of a screen are its size, the type of scan with the the image to be projected, the image refresh rate, and the distance from which the image is viewed. herself.
| HD | Full HD | |
|---|---|---|
Definition |
It is the high definition resolution of a screen that has 1280 horizontal pixels by 720 vertical pixels. |
It is the high definition resolution of a screen that has 1920 horizontal pixels by 1080 vertical pixels. |
Characteristics |
|
|
Other denominations |
High Definition, HD Ready, 720p. |
Full High Definition, HD Ready 1080p, True High Definition, 1080p. |
Image size |
1280 x 720 = 921 600 0.9 megapixels. |
1920 x 1080 = 2.1 megapixels. |
| Approximate ideal viewing distance | Minimum distance of 3 m for a 50-inch screen. | Minimum distance of 2 m for a 50 inch screen. |
| Ultra hd | 4K | 8K | |
|---|---|---|---|
Definition |
It is the ultra high definition resolution of a screen that has at least 3840 horizontal pixels by 2160 vertical. |
It is a resolution used in film production and projection, known to have 4096 horizontal and 2160 vertical pixels. |
It is the ultra high definition resolution screen that has 7680 horizontal and 4320 vertical pixels. |
Characteristics |
|
|
|
Other denominations |
4K, UHD, Ultra HD, UHDTV. |
DCI 4K. |
8K UHD, Full UHD, Full Ultra HD. |
Image size |
3840 x 2160 = 8.3 megapixels. |
4096 x 2160 = 8.8 megapixels. |
7680 x 4320 = 33 megapixels. |
| Approximate ideal viewing distance | Minimum distance of 1 m for a 50-inch screen. | Minimum distance of 7.7 m for a cinema screen of about 10 m. | Minimum distance of 50 cm for a 50-inch screen. |
What is resolution?
The resolution of a screen refers to the level of definition offered by television, computer or mobile screens, as well as projectors. This is measured as a function of the number of pixels that the screen has width and height. For example, a high definition or HD resolution screen is 1280 x 720 pixels.
Resolution and number of pixels
Apixelis the minimum or basic unitwith which a color is represented on a screen. In other words, a pixel is each one of the "squares" that can be observed when an image is magnified.
Now, the resolution of a screen is expressed in pixels, which are presented as the number of pixels across the width and height of the screen. As a general rule, how much the higher the resolution that has a screen (number of pixels), the higher is its definition.
Thus, on two screens with the same size, but with different resolutions, the one with a higher resolution will have more pixels and the screen with a lower resolution will have fewer pixels.
In addition, to know the resolution of a screen, the horizontal lines that it has are counted. Each horizontal line represents the measurement of one pixel high. For example, a 1280 x 720 screen has 720 horizontal lines.
Interlaced scan and progressive scan
Thesweep, scan, or interlaced scan (interlaced scanning) refers to the presentation on the screen of an image that is divided into two different parts or frames intertwined, and is described by the letter "i" (as in 1080i).
Each frame consists of a series of odd or even horizontal lines. Odd lines are projected first, left to right and top to bottom, followed by even lines. This process is carried out at very high speed, at 1/60 of a second, so it is not perceptible to the naked eye.
If a screen has a resolution of 1080i, this means that it has 1080 horizontal lines. However, the total of the even lines (540 lines) are part of one frame, while the total of the odd lines (540 lines) are part of another.
Interlaced scanning was used in the past to transmit the analog television signal. However, it began to fall out of use today. One of its biggest disadvantages is that the displayed image is incomplete, as it is composed of two different frames, producing the appearance of “ghost” images.
Progressive scan, scan or sweep (progressive scanning) refers to the presentation on the screen of a complete image that is not separated into different frames. The letter "p" is used to identify if a resolution has progressive scan, along with a description of its size. For example, a 1080p resolution has a progressive scan.
In this case, progressive scan means that each horizontal line is scanned in sequence. Thus, the screen projects one by one the lines from top to bottom in order and the image they form corresponds to a frame.
Refresh rate of a screen
Update frequency of a screen (refresh rate) refers to the number of frames that a screen is capable of displaying in one second. This frequency is measured in hertz (hertz) or cycles per second.
A screen capable of updating 120 frames per second, is a screen that has a refresh rate of 120 Hz. Similarly, if a screen has a frequency of 60 Hz, the refresh rate of this screen is lower than that of a 120 Hz.
The speed with which the screens refresh the images is related to the resolution of the screen, since, the higher the refresh rate, the sharper and more fluid the video will be seen.
Resolution, screen size and viewing distance
Both the size of a screen and the distance from which the content that it displays is viewed are key elements that influence the way a given resolution is appreciated. As a general rule of thumb, the higher the resolution, the closer the images can be viewed on a screen without the pixels showing.
The size of television screens and monitors is measured by their diagonal length. If a television has a 14-inch screen, this means that there are 14 inches on the diagonal from one corner of the screen to the other.
As a general rule, the higher the resolution of a screen (more pixels it has), the closer you can be to it without losing the image definition. On the contrary, the lower the resolution of a screen (fewer pixels it has), the further it will have to be viewed from a distance so as not to lose definition.
What is HD?
Abbreviations HD or High Definition describe the resolution of a high definition display of 1280 x 720 pixels. The total number of pixels of these displays 921 600 (about 1 megapixel). This resolution is also known as 720p.
The “p” added to the 720p description indicates that the device or TV screen scans the images progressively.
HD resolution may also be described as HD Ready (HD ready) on different devices. In this case, HD Ready indicates that these devices offer a resolution of at least 720p.
HD resolution has an aspect ratio of 16: 9, between the width and height of the screen. This aspect will be the standard used for the next generations of higher resolution screens.
Regarding the relationship between the screen size and the minimum ideal visual distance, it is advisable to use screens that are not very large if their resolution is simply HD or 720p, or view them from a larger distance.
Thus, if a television has a size of 20 inches and has a resolution of 720p, the minimum recommended distance to be able to enjoy this quality would be 1.2 m. If the screen is observed closer to this distance, the pixels that make up the image will become evident, reducing the definition of the image.
720p HD displays are falling out of use and popularity, due to higher resolutions being offered on the market at relatively low prices.
What is Full HD?
The description Full HD, or true or full high definition, indicates that the resolution that a screen is capable of offering is 1920 x 1080 pixels.
Full HD resolution is also known as 1080p, since it has 1080 horizontal lines. The "p" refers to the fact that the scan made of the image is progressive. As in the case of 720p HD screens, it is also possible to find Full HD screens with the designation of HD Ready.
Possessing 1920 x 1080 pixels, the Full HD resolution has a total of 2,730,600 pixels (2 megapixels). This means that a resolution of 1080p is higher than a resolution of 720p, since it has an amount of more than double pixels.
For example, if there are two displays, each 55 inches diagonally, and one is 720p or HD, while the another is 1080p or Full HD, the latter would have more pixels over the same area, which leads to a greater definition.
Another advantage that Full HD resolution offers over HD resolution is that the screen can be of a larger dimension without losing quality. For example, if a television screen in Full HD is 20 inches, the minimum distance at which it can be observed without perceiving the pixels is 0.80 cm.
Full HD resolution is one of the most common in televisions, monitors and projectors and has an aspect ratio of 16: 9.
What is Ultra HD?
Ultra hd It is a resolution that is commonly associated with 4K resolution. However, these resolutions are different from each other. Ultra HD or Ultra High Definition resolution refers to that resolution that reaches at least the 3840 x 2160 pixels and that saves a 16: 9 aspect ratio on the screen.
The name “Ultra HD” was adopted in 2012 by the Consumer Electronics Association (CEA). This screen resolution is the next step after Full HD or 1080p resolution.
With 3840 x 2160 pixels, or 8,294,400 total pixels (over 8 megapixels), the Ultra HD resolution is four times higher than Full HD (1080p) and nine times higher than HD resolution (720p).
On many occasions Ultra HD resolution is confused with 4K resolution. This confusion occurs mainly for two reasons: on the one hand, due to a marketing issue and, on the other hand, because the number of pixels that the Ultra HD resolution has across the width (2840) of the screen is close to 4000 pixels.
The scan that uses this resolution on the screen is progressive. Unlike 1080p resolution, this detail is omitted most of the time in the forms in which it is marketed (UHD, 4K, UHDTV).
Regarding the transmission and consumption of the television signal or online content in Ultra HD, one of the major problems is the consumption of bandwidth that this requires to be able to transmit video in a fluid. The transmission must be of high speed and it is necessary to have a plan that covers the transmission of this type of resolution quality, which is not always accessible to all audiences.
Regarding the viewing distance and the size of the screen, if it is 40 inches and has Ultra HD resolution, the minimum distance in which a good definition could be seen would be about 80 cm.
What is 4K?
The denomination 4K refers to a resolution standard of 4096 x 2160 pixels that was developed by the Digital Cinema Initiatives (DCI) for use in film production, both in projection and on cinema screens.
It is known as 4K because of the 4096 pixels that make up the width of the screen, or projection of the image in the cinema. It has a total number of 8,847,360 pixels (almost 9 megapixels).
This resolution format is the successor to 2K (also used as a standard in cinema), which has a resolution of 2048 x 1080 pixels or 2 211 840 total pixels. Thus, 4K resolution has four times more pixels than 2K.
The main aspect ratio of this type of resolution is 1.90: 1 (4096 x 2160, known as full frame). However, it is possible to find other aspect ratios, such as 1.85: 1 (3996 x 2160) and Cinemascope or 2.39: 1 (4961 x 1716).
What is 8K?
8K refers to the resolution of 7680 x 4320 pixels on a television screen, monitors, and other devices. The 8K receives this name from the count of pixels arranged across the screen, which is 7680.
Despite its name, 8K resolution, it is the generation that follow Ultra HD resolution of domestic consumption and not of the 4K resolution used in projection within the film industry (DCI 4K), hence it is possible to find it cataloged as Full Ultra HD.
Regarding its size, the 8K resolution has a total of 33 117 600 pixels (33 megapixels), being four times larger than the number of pixels that Ultra HD has and 16 times higher than HD.
This resolution offers the higher definition of commercially available resolutions, offering a high degree of immersion. However, it is still not very accessible to the general public, due to its high prices. In any case, it is likely that in the near future it will start to become popular, as Ultra HD resolution did in recent years.
The scanning of this resolution is progressive, although, as in the case of Ultra HD, it is not common to use horizontal lines to identify it (4320p).
Regarding the aspect ratio used by 8K, this is 16: 9, so all high-definition series continue to favor this aspect, at least when it comes to televisions.
It is worth mentioning that to transmit a television or video signal in 8K resolution, you need a high speed service (50 Mbps) and a wide bandwidth. For this reason, 8K resolution displays are some of the most expensive on the consumer market.
As for audiovisual programming and production for this type of screen, it is very limited. However, 8K displays may be able to scale content produced in 4K, so the range of consumable production is as wide as that created for 4K displays.
Thanks to its high resolution, the minimum viewing distance to observe a 40-inch 8K screen, without losing quality in its definition, is about 45 cm.
Other screen resolutions
Outside of high definition resolutions, different resolutions have existed throughout the history of analog and digital television.
In the case of analog resolutions television standard, the best known are the PAL and NTSC. These standards have been used for a long time in broadcasting television around the world.
The resolution NTSC (acronym that refers to the United States National Television Standards Committee) was used mainly in the United States, Central America and some countries in Asia. The NTSC resolution is composed of 720 x 486 lines, with as well as a 4: 3 aspect ratio and a 50 Hz refresh rate.
The resolution PAL or alternate phase line, is a format that has been widely used worldwide. This resolution consists 720 x 576 lines and an aspect ratio of 4: 3, with a refresh rate of 60 Hz.