4K Resolution TV Everything You Need to Know

4K Resolution TV Everything You Need to Know

 

4K technology is quickly taking over the mainsteam of the digital video world, from TV screens to computer monitors to cameras and projectors, 4K screen resolution and all of its accompanying features are now no longer just bleeding edge technologies but becoming positively mainstream, particularly when it comes to TV displays and the video recording that creates their content.

With four times the resolution of traditional HD displays, 4K Ultra HD offers a massive improvement in picture clarity over existing HD resolutions.

The reason for this has to do with the amount of pixels a 4K TV contains. Whereas traditional HD is limited to 1920 vertical columns and 1080 horizontal rows of pixels, Ultra HD has a total resolution of 3840 pixels by 2160 – a slightly smaller resolution than the 4,096 x 2,160 resolution seen on cinema screens (that, for the record, is called Cinema 4K).

What is 4K?

Pure and simple, 4K means a clearer picture. It's more pixels (8,294,400 to be exact) on the screen at once that creates images that are crisper and capable of showing more details than standard HD.

What is the resolution of 4K?

4K resolution, at least the way most TVs define it, is 3840 x 2160 or 2160p. To put that in perspective, a full HD 1080p image is only a 1920x1080 resolution. 4K screens have about 8 million pixels, which is around four times what your current 1080p set can display.

Think of your TV like a grid, with rows and columns. A full HD 1080p image is 1080 rows high and 1920 columns wide. A 4K image approximately doubles the numbers in both directions, yielding approximately four times as many pixels total. To put it another way, you could fit every pixel from your 1080p set onto one quarter of a 4K screen.

Why is it called 4K?

Because the images are around 4,000 pixels wide. And before you ask, yes, the industry named 1080 resolution after image height, but named 4K after image width. For extra added fun, you also might hear this resolution referred to as 2160p. Welcome to the future. It's confusing here.

Do all those extra pixels matter?

They matter very much. More pixels means more information. More information means sharper pictures. Sharper pictures are more engaging. More engaging content is more fun. And fun... well fun is the thing, isn't it?

Moving 4K into Home Theater

While the origins of 4K film go back quite a ways and have their roots in theatrical releases of films such as Blade Runner: The Final Cut back in 2007, it wasn’t until James Cameron filmed his now famous “Avatar” in 4K resolution that the projection platform itself was widely introduced in many theaters eager to please audiences with beautiful crystal screen clarity.

However, going from theaters to something like home entertainment is a big leap and it wasn’t until just within the last couple of years that both projectors and the already mentioned TVs became widely available for home theater system set up that would let consumers enjoy UHD clarity in their houses.

Now, in terms of TV 4K systems, this resolution isn’t even entirely noticeable unless you enjoy a very large and thus very expensive screen or are sitting abnormally close to your TV. However, when it comes to projectors, the power offered by 4K really does become visible.

Sitting close enough?

Yup. Remember when Apple made a big fuss about "retina" displays a few iPhones back? "Retina" refers to screens that have sufficient resolution that at a normal viewing distance your eye can't make out individual pixels. Get far enough away from a 1080p set and, hey presto, It's a retina display! More importantly, at that same distance, your eyeballs won't be able to squeeze any more detail out of a 4K image than a 1080 one. If you're at "retina distance" from your 1080p set now and don't plan on moving your couch closer, upgrading to 4K may not make a big difference to your experience.

So I should sit closer?

Oh my yes. The ability to get up close to the screen without the image breaking down is one of the most intoxicating things about 4K. Sitting closer allows the same sized screen to fill more of your visual field, which yields greater immersion. The up-close factor is one of the reasons 4K computer monitors have become one of the technology's fastest growing sectors. 4K monitors remain pin-sharp even when you're just a foot or two from the screen, as you are when you're sitting at your desk. 

Streaming 4K Content

While 4K content for home theater systems such as projectors and TVs is still pretty scarce on the ground, it is making ground as streaming content. YouTube has had a 4K channel running since as early as 2010 and other developments are definitely on the horizon, especially in countries or regions with excellent internet connectivity that goes above the normal speeds available to most people.

The broadcast industry as a whole is offering the promise of a steadily more established standard in streaming content compression during transmission, called H.265 or HVEC (High Efficiency Video Codec). With the implementation of HVEC, broadcasters are assuring the buying public that 4K content will become easy and economical to stream into home theater systems and thus will become much more common. TV manufacturers themselves have been keeping up to date with this promise and have ensured that every new 4K TV to be released since 2015 and today, as well as for the foreseeable future, is fully capable of decoding the HVEC standard for its users.

Furthermore, other competing standards of 4K video compression are being developed, though with less ecosystem traction. One that has gained some headway is Google’s VP9 4K video compression codec, which the company still uses in compressing the 4K content streams found on its YouTube video service. Most premium 4K TVs today are compatible with both VP9 and H.265, though not all models offer both.

Specific 4K display-related technologies

Moving along into some particular features of current 4K display features in TVs and other devices, we come to a few very particular specs and technologies which are redefining the quality of both the TV display viewing experience and how rich the consumer content experience can become. In particular, high dynamic range and wide color gamut are playing a crucial role in making 4K TVs into displays of previously unparalleled richness and quality.

High Dynamic Range

High dynamic range technology is the Big New Thing in the world of 4K TV displays and with good reason. What HDR essentially does is expand the range of both bright and dark levels a 4K TV can show on the screen. At the same time, highlights of color vibrancy and richness are also expanded by this same wider dynamic range. The result is a more realistic, much more sharply detailed picture quality in comparison to what you’d see with standard dynamic range (SDR).

Of particular interest to TV makers (and consumers once they get to experience the realism produced) is the ability to develop HDR that can come as close as possible to simulating the brightness and darkness of the real world. Thus, while we already have 4K TVs that can create essentially “perfect” darkness with no notable light emission, in the form of OLED technology, the brightest consumer HDR 4K televisions, even for 2016, can only manage something between 1000 and 2000 nits of brightness, when in the real world, even the sky on a sunny day is seen by our eyes at about 20,000 nits. Thus you can see the dramatic difference at work here.

However, the aim of 4K TV makers and the companies behind HDR technology is to create displays which can even reach 10,000 nits. This is what one HDR standard bearer called Doby Vision is aiming for. Current HDR standards like “UHD Premium” from the UHD Alliance call for at least 1100 nits of maximum brightness in LCD 4K TVs but more on that shortly.

Wide Color Gamut

Another crucial aspect of modern 4K TV content is color gamut technology, or the ability to deliver the largest possible range of rich colors for the greatest possible realism and vibrancy. Currently, many 4K TVs are thus starting to offer color ranges that conform two two particularly broad gamuts called DCI P3 (which is frequently used in commercial cinematic display) and REC.2020, which is the current “Wide Color Gamut” gold standard for 4K ultra HD. However, not all 4K content fits these higher quality standards and much of the video and 4K TV display technology still on sale is REC.709, which was developed for older HDTV display technology.

Devices, such as 4K HDR TVs

• ·       Display resolution: minimum of 3840 x 2160 pixels
• ·       Color bit depth: 10-bit signal
• ·       Color Palette: (Wide Color Gamut)
• ·       Signal Input: BT.2020 color representation
• ·       Display Reproduction: More than 93% of the DCI P3 color spectrum
• ·       High Dynamic Range
• ·       SMPTE ST2084 EOTF
• ·       Both Peak Brightness and deep black levels of either more than 1000 nits and less than 0.05 nits of black, OR more than 540 nits of peak brightness and less than 0.0005 nits of black level. (This dual contrast standard is likely a direct sop to LG’s OLED technology, which can’t match the high nit levels of LCD/LED displays but can completely outmatch them in terms of how dark their blacks go, thus re-bracketing the range which constitutes HDR and deep contrast.

 My friend told me about 4K OLED. What's that?

More acronyms! Isn't this fun? OLED - organic light emitting diodes - have been around for some time, but producing big screens using this technology has proven to be prohibitively expensive, something which has so far prevented OLED television from being a mainstream proposition.

It's a real shame because OLED technology can be stunning, offering vibrant colors, deep blacks and bright whites. But don't give up hope just yet. Several companies (most prominently LG) are laboring away to bring OLED to 4K televisions. We recently took a look at LG's new 4K OLED sets, but while they're gorgeous, pricing remains sky high. Hopefully that will change soon, though. "I believe the price and yield rate will be higher immediately and the price will be down," Mr K I Kwon, president of LG Electronics UK, told recently. We hope his predictions hold and we aren't ruling out OLED as a big player in the next generation of televisions.

What about 4K content? Can I get that?

Yeah, about that... There's actually not much 4K broadcast content to be had right now. That said, if you're willing to shell out for it – e.g. buy a 4K UHD Blu-ray player and several 4K Blu-ray discs or purchase digital UHD movies outright from services like Sony's Ultra Streaming Service or UltraFlix – there are plenty of other options out there.

Why isn't broadcast TV in 4K?

Because every 4K frame contains four times the information of HD, 4K content is four times more bulky than regular HD content in terms of its raw file size. That makes it a challenge to get it to you. Broadcast TV hasn't made the 4K switch yet (indeed, it's only recently that hard drive sizes have gotten big enough to manage DVRing HD programs comfortably).

But you can get 4K Blu-ray discs should you decide to buy a Ultra-HD Blu-ray player.

What about gaming in 4K?

We've had 4K gaming on the PC for a while now, but this year at E3 2016 4K took off in a big way with the announcement of Microsoft's 4K Xbox code-named Project Scorpio. Alongside the Scorpio, Microsoft also has the Xbox One S which will upscale HD content to 4K as well as play Ultra HD Blu-ray discs.

Microsoft isn't the only console manufacturer with a 3840 x 2160 resolution on its mind, however. Sony just announced a 4K console of its own called the PS4 Pro that not only plays 4K Ultra HD movies and TV shows from streaming services like Netflix, but can play games in 4K, too.

What kind of cables will I need for 4K?

The two standard cables you're most likely to use are either a standard HDMI or if you're connecting a PC to a Ultra HD monitor, Display Port.

HDMI cables now come in four flavors: high speed with ethernet; high speed without ethernet; standard speed with ethernet and standard speed without Ethernet. Standard speed cables are capable of 1080i, but aren't able to handle the bandwidth of 4K. High speed cables can do anything higher than 1080. Now, as long as you're using the same class of cable, there is no distinguishable difference in terms of performance between one manufacturer's set of cables and another's.

The speed of your connection will depend on the types of connectors, which includes HDMI 1.4, HDMI 2.0 and HDMI 2.0a. HDMI 1.4 connectors support a 3820x2160-resolution at 30 frames per second, while HDMI 2.0 is the latest spec and can output video at Ultra HD resolution at 60 frames per second. (But more on that below!) HDMI 2.0a is capable of HDR, which is limited to a very specific range of televisions from each manufacturer.

The other type of cable you can use is DisplayPort. DisplayPort carries 4K image and audio signal from most high-end graphics cards to monitors without any noticeable artifacts or delays.

So should I buy a 4K set now or should I wait?

It depends. If you want the absolute best TV you can get right now and don't mind paying a premium for it, it's a 4K set. If you're buying from one of the top tier manufacturers, you're going to get a good product that's reasonably future-proofed. As we said before, the sets look great. However, don't expect to be watching most of your video content in 4K for another two to three years. And make sure any set you buy has HDMI 2.0 ports (the first wave of 4K TVs used the previous HDMI 1.4 standard).

On the other hand, if you're price sensitive or want to wait until the content side of the equation is a bit more solved, it absolutely makes sense to wait. The UHD Premium specification is still in its infancy, and although we're moderately sure and it remains to be seen if the entire industry will eventually adopt it.

In terms of content you're not missing out on much at the moment. There are incredible values to be found in generously-sized 1080p sets right now. And 4K sets are only going to get cheaper.

What’s the Bottom Line, Is 4K Here to Stay?

This certainly looks to be the case. Current 4K UHD trends are developing at a much faster and steadily more affordable pace than what we’re seeing with plasma TV and the still incredibly expensive OLED display technology. In fact, plasma TVs, which for a time were thought to be the next wave in Ultra HD TV display technology are failing completely so far. With Their main manufacturer having ceased production this year.

This means that 4K is almost certainly going to have its large space on the TV market as new UHD content emerges, and the technology is already well established as the latest and possibly best in cameras and film projectors.

Yes, major manufacturers are already working on experimental development projects in the even more powerful 8K resolution technology but many of the problems that already exist with displaying and streaming 4K will need to be worked out even further before 8K ever becomes a commercial product. So for now, it seems that 4K is here to stay at least for the next few years and getting ready for it is a great idea now that prices for TVs, cameras and even projectors are dropping.

Pros

1) The 4K TV is gorgeous because of its resolution 3840×2160 which gives perfect image clarity. The pictures are more detailed with sharpness.

2) The image depth is so nice that it overcomes the problem of some people who feels that the image is getting flattened. Every image is clearly seen in this 4K TV.

3) 4K TV can handle the perfect color of an image. Even if the picture is heavily compressed the color won’t change. Color resolution plays good in 4K TV.

4) 4K TV will make the view of 3D better because of its bigger screen resolution. You may feel real 3D image with this TV.

Cons

1) You may only feel 4K presence if the screen you choose is big.

2) 4K TV is more expensive and we need to buy some extra devices based on the purpose.

3) 4K TV sources are still short due to the broadband and Blu-ray disc connectivity  problems.

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The advantage of H.265 Camera

H.265 / HEVC is the latest video compression standard which is based on H.264, driven by ever increasing demand for high definition and the rapid development of imaging technology, UHD becomes trend in today's television and video surveillance market. UHD standards for ultra high definition includes 4K UHD and 8K UHD. 4K UHD equals 3840 x 2160 (approximate 8.29 megapixels), while 8K UHD equals 7680x4320 (approximate 33.18 megapixels). 

In today's video surveillance applications such as parking lot, hotel, safe city, harbor, air port and elsewhere large scaled and has growing demand on detail capturing, which, at the same time, pressuring on decoding and storage. Apparently, the introduction and development of H.265 standard brings extensive possibilities and optimism to the industry by addressing problems such as shortage of bandwidth, improving transmission efficiency and delivers other benefits.

In order to solve the high bandwidth problem for ultra high definition, the Moving Picture Experts Group (MPEG) developed the H.265/High Efficiency Video Coding. Compared with current mainstream H.264/MPEG-4 AVC, the H.265 is able to double the data compression ratio, while improve video quality with low bit-rate. The H.265 supports both 4K UHD and 8K UHD resolution up to 8192x4320. In conclusion, H.265 is capable of further reducing 50% the data rate requested for high quality video coding. Bitrate is acclaimed to have approximate 40% to 50% down at 1080p while rendering superb image quality.  This enables IP camera to deliver smooth video with low bandwidth, which in turn, reducing the network bandwidth, and video storage size. Meanwhile, with the rapid development of 4G cellular mobile technology, the integration between the H.265 and 4G will have much possibilities.

HEVC/H.265 mainly features in the following aspects:

·         Higher compression efficiency, when compared with H.264/AVC. In same resolution, HEVC/H.265 has lower bitrate than H.264/HEVC.

·         Support high definition, ultra high definition video formats

·         Support frame rate of 20-60 frame per second video decoding, has same flexibility like the H.264/AVC, supports maximum 172fps.

·         Friendly network adaptation.

As leading and innovative corporate, Hisilicon and Ambarella can't resist its charm and prospect, both of them introducing the first H.265 SoC for ultra high definition IP cameras. Despite the reason that H.265 is still a new compression standard to video surveillance industry, the security camera manufacturers such as Hikvision and Dahua have already adopted H.265 in their latest product portfolio, including ultra high definition network camera, NVRs.

To start with cameras, Hikvision has a latest-released 2 megapixel H.265 low light smart camera DS-2CD5026FWD-(A)(P). As H.265 camera, the Darkfighter series ultra-low light Smart cameras are able to capture high quality colored images in dim light environment. DS-2CD5026FWD offers Full HD resolution with up to 60fps high frame rate, 120dB WDR, Auto Back Focus, P-Iris, PoE, 3D DNR and complete Smart Feature-set to meet a wide variety of applications. It supports H.265/H.264/MJPEG dual video compression, allowing over 40% lesser bandwidth use while acquiring outstanding image quality. Moreover, with its functions such as Intrusion Detection, Line Crossing Detection, Scene Change Detection, Audio Surge Detection, Audio Loss Detection, Defocus Detection, Face Detection, etc.

On video storage perspective, Dahua and Hikvision introduced a comprehensive H.265 4K NVR product lineup, which covers different demands from small to medium as well as large scaled applications. These network video recorders have capability to support up to 12 megapixel recording capability, supporting 1080p@60fps and H.265 preview and playback; 4 channel 4K resolution real time live view and playback; meanwhile, the NVR has many intelligent functions including smart video analysis, facial detection, privacy mask.

4320p, 2160p, 1080p & 1080i, 720p & 720i, 576p & 576i, 480p & 480i, 360p, 240p

4320p:

4320p is an alternative name for 8K UHD, a resolution planned to appear in future UHDTV products. The number 4320 stands for 4,320 lines of vertical display resolution, while the letter p stands for progressive scan or non-interlaced. In a progressive image, the lines of resolution of the image go from the top of the screen to the bottom.

It is 7680 × 4320 (33.1 megapixels in the 16:9 aspect ratio).

2160p:

2160p is an alternative name for 4K UHD, a resolution supported by UHDTV products and which offers four times the definition of 1080p. The number 2160 stands for a display resolution which has 2160 pixels along the shortest side, while the letter p stands for progressive scan or non-interlaced. In a progressive image, the lines of resolution of the image go from the top of the screen to the bottom.

2160p or 4K UHD is 3840×2160 (8.3 megapixels in the 16:9 aspect ratio) 

1080p & 1080i :-

1080p (also known as Full HD or FHD and BT.709) is a set of HDTV high-definition video modes characterized by 1080 horizontal lines of vertical resolution and progressive scan, as opposed to interlaced, as is the case with the 1080i display standard. The term usually assumes a widescreen aspect ratio of 16:9,

1080p & 1080i is 1920x1080.

720p & 720i

The number 720 stands for the 720 horizontal scan lines of image display resolution (also known as 720 pixels of vertical resolution), while the letter p stands for progressive scan (i.e. non-interlaced) & i is interlaced, as is the case with the 720i display standard.

720p & 720i is 1280x720

576p & 576i

576p is the shorthand name for a video display resolution. The p stands for progressive scan, i.e. non-interlaced, the 576 for a vertical resolution of 576 lines, usually with a horizontal resolution of 720 or 704 pixels. i stands for interlaced.

480p & 480i

480p is the shorthand name for a family of video display resolutions. The p stands for progressive scan, i.e. non-interlaced. The 480 denotes a vertical resolution of 480 pixel high vertically scanning lines, usually with a horizontal resolution of 640 pixels and 4:3 aspect ratio. i stands for interlaced.

360p

This is an Animoto video’s default resolution. The majority of YouTube and Hulu videos are displayed in 360p, so that’s about the video quality that 360 lines of resolution provides. This (as well as the 480p) is a great resolution for mobile devices since the mobile screen rarely has enough pixels or enough memory to support HD videos.

240p

Low-definition analog TV systems. Mobile DTV systems. small screens (320 × 240 and 480 × 272 pixels respectively).

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To 4K or not 4K video or Ultra HD

To 4K or not to 4K video or Ultra HD

Our industry’s seemingly insatiable appetite for more and more resolution has now produced a wave of interest in 4K cameras that promise exceptional clarity and sharpness, akin to the big screen, Ultra HD television sets found in consumer electronics stores and an increasing number of North American homes.

The jury is still out on whether there is an immediate need for the resolution that can overcome the downsides of increased storage and bandwidth required for running 4K cameras in a surveillance operation. Like so many things, if the cost of the camera, cost of the supporting system infrastructure and components were of no concern, this new format would likely be a more viable and attractive option for many security applications.

Here are four things to consider before making the leap to investing in and deploying 4K video:

1. What will I get with 4K that is not possible at lower resolution?

There’s no doubt that 4K technology is light years ahead of analog quality, but the reality is that the increased clarity and sharpness provided by that level of resolution is often over and beyond what is required and able to be managed by a typical security operation. For many reasons, full HD/1080P is the most commonly used resolution for new systems. The majority of security systems in use for live monitoring situation do not really benefit from such a resolution, as the human eye is well served with the details of a 1080P picture. Higher resolutions pay out when more details are required in forensic investigations.

2. Double the resolution, double the processing requirements

Users typically want to see more than one camera on one monitor, and only  occasionally switch to full screen modes. With 4K, the clarity of that multi camera view would be no clearer than what would be viewed from a lower resolution camera. In addition, delivering streams from multiple 4K cameras presents some technical challenges. The client PC and graphics card must handle a significant flow of data. The best approach is to have the live view limited to only enough resolution for the video size and screen resolution of the display.

Today a typical approach to balance PC power requirements and quality uses lower resolution streams for live view, while recording in the highest resolutions. 4K resolution taxes the workload on the network because recording the highest resolution means the full stream content moves from the camera to the NVR.

3. Limitations on form factors, lenses

The availability of affordable high resolution optics is just not there yet, and a dome style camera with a typical curved dome bubble cannot transmit the 4K resolution. In addition, a true 8MP resolution lens with appropriate coverage for the 4K sensor is quite large, which would render a 4K version of the compact dome camera (the market’s favorite form factor) essentially not possible.  The dome camera would get physically bigger which, for many customers, is a negative.

4.  Bandwidth and storage requirements

From a cost perspective, quadrupling the resolution from full HD to 4K won’t quite double the camera price. However, on the recording side it will most definitely demand more than double the storage requirements when operating under the same conditions.

Bandwidth consumption is related to processor power available on the camera. For example, the average full HD cameras deliver about 6Mbps at 30 ips. On the bright side, some manufacturers are offering full HD models with advanced compression capabilities that can reduce bandwidth consumption to about 3Mbps, with the next iteration to handle 4K video at full HD bandwidth consumption levels. Additionally new compression standards such as H.265 HVEC (High Efficiency Video Encoding) will make higher resolution bandwidth more practical for surveillance.

So where does this leave you, 4K today or not just yet? For some customers a bigger number is frequently perceived as a better solution but surveillance installations should focus on the reason the system investment is being made in the first place; protection of personnel and protection of assets. It is far from a one size fits all decision and resolution is an important tool in the system solution.

Next benchmark for video surveillance cameras is going to be the Ultra HD standard, with a resolution of 3840 x 2160 – around 8MP. Given the challenges networks may face carrying Ultra HD video streams it’s hard to say just when we will see the technology reach a tipping point.

THERE are a couple of signs worth paying attention to with Ultra HD (commonly called 4K in consumer and CCTV industries). The first is that UHD consumer monitors, which are now dropping in price at a time many homeowners’ first 1080p HD monitors may be starting to look a little tired. Something else to bear in mind is the consensus forming in digital photography that 8MP is the sweet spot that allows the best balance of low light performance and high resolution.

As most readers know, the more pixels you cram onto an imager, the smaller those pixels must be. And the smaller the pixels, the less light they can absorb. Double the number of pixels on a 1/3-inch HD sensor and you halve the light reaching the sensor. The result is that more pixels does not a perfect camera make – not unless sensor sizes increase. If it’s all about display images today, then 3MP cameras with a 1080p resolution are ideal.

But if you need digital zoom or you use a UHD monitor, then Ultra HD cameras should be a consideration. If you zoom in 2x digital with an Ultra HD image then you are viewing at 2MP, which is pretty good considering how quickly it takes an HD camera to burrow down under 4CIF when digital zoom is applied. 

Something else to bear in mind when considering digital image quality is that pixels on a digital camera’s sensor capture light in red, blue or green – not all colours at once. A layout will be a pair of green, a red and a blue in a grid pattern and onboard software then nuts out the colour value for pixels. This means there’s signal attenuating averaging going on in the background - one colour per 4 pixels.

A camera’s digital engine is also working hard to stave off false colours and moire – spacial aliasing that causes false patterns in a scene. Camera engines will blur an image slightly then sharpen it in order to lose such artifacts. Clearly, the more pixels, the more work the camera processor has to get through and this can be noticeable as latency or blurring if there’s sudden movement – like cars moving at right angles across a scene.

Lenses are another issue. An Ultra HD camera is going to need a quality lens and there’s no doubt that plenty of 1080p cameras are being sold with lenses that are not perfect. Sure, things look good in the centre of the image but out towards the edges details get muddy, especially on the sorts of deep zooms that might motivate a buyer to choose Ultra HD in the first place.

Sensor noise is also something that has to be considered at multiple levels. In low light, cameras increase exposure, elevating noise levels. Furthermore, pixel measurements are never perfect and the flaws in these signals show up on a monitor as noise. It’s unhelpful during the day and blinding at night. Digital noise reduction is the answer but DNR processing doesn’t just lose noise, it sloughs fine detail off a scene. When you look at a camera being tested in low light you can often see the areas where DNR has scrubbed and smudged a scene free of detail. It’s not a good look.

Engineers can build high resolution imagers with fewer noise problems but they need to be big – 1-inch or 1/1.5 inch sensors are ideal. A 1/1.5-inch sensor has 4x the area of the 1/3-inch sensors that typically run inside 1080p CCTV cameras. No wonder GBO’s S1080 camera (BGWT sells them in Australia) with its monster 1-inch sensor has such a great image in low light.

If the sensors are large enough, the lenses are good enough, the network is capable enough and the storage sufficient, then Ultra HD cameras will give end users a lot more detail than 3MP 1080p cameras can. But this capability has to be balanced against many things. Image quality is about more than megapixel count. 

“If a sensor is of the similar size as the equivalent HD sensor and it has 4x the pixels - low light performance will be 4x lower. And streaming bandwidth will be close to 4x larger unless better compression is used”

Keep in mind,

4K =     8.3 megapixels, aspect ratio 16:9 Horizontal resolution

1080p= 2.1 megapixel,  aspect ratio 16:9 Vertical resolution

720p=   1.3 megapixel,  aspect ratio 16:9 Vertical resolution

D1=      0.4 megapixel,  aspect ratio   4:3 Vertical resolution