[英语论文代写 Li]

HDR, which is short for high dynamic range, is a term you’ve likely heard before if you’ve been shopping around for a new TV for your home.

But it’s rarely explained – at least not fully enough for most of us. You probably know it’s something good to have on your new TV, but you’re probably less sure exactly what it refers to. We like to think of it a bit like the audio-visual (AV) world’s equivalent of ‘organic’.

What’s important is that HDR could change the way you watch TV – and even movies on your phone too – for good.

To begin let’s look at 4K TVs. 4K TV displays tend to get most of the attention these days, as they produce four times the number of pixels of any HD TV on the market. But is more necessarily better? Do you care how many pixels there are if none of them look any good?

This is where HDR comes in. What HDR does is get more dynamic pictures and quality out of those many, many pixels. What that means for you and your viewing experience is that with an HDR TVs bright whites look brighter, dark blacks look darker, and 10-bit panels are finally able to display the 1 billion colors you’ve been wanting to see.

So, in short: 4K describes the quantity of pixels, but it’s HDR that describes their exceptional quality.

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[英语论文代写 Li]

What is HDR?

HDR is used in a few different contexts.

So let’s clear up some confusion first: the kind of high dynamic range that your HDR TV is capable of shouldn’t be confused with the HDR photography options that have recently been added to smartphone cameras.

They are similar. Both result in images that have a greater contrast between light and dark. But the way they work is slightly different.

For example, high-end cameras and recent smartphone apps utilize HDR by combining several photos taken during a single burst of many photos.

Separate photos are taken at different exposures during the process. These are called stops, and the amount of light is doubled from one to the next. So while the first stop produces an extremely dark image, the last result is exceptionally bright, lending better luminosity to the final portmanteau photo.

But that’s not the same for video.

Yes, you’re still getting an expanded color gamut and contrast ratio when it comes to video, but you’re not doing it by combining several images or videos. It all has to do with the way an image is displayed on the screen and the source content used to do it.

So while it shares a name and some common points with photography, clearly HDR video is different to smartphone photography.

The end result, an image with more contrast between its lightest and darkest areas is the same, but instead of combining separate images this effect is produced using better camera technology to capture the best possible footage in the first place.

[英语论文代写 Li]

The improvements you’ll see with an HDR image compared to a normal image are numerous.

Whereas on a standard display everything below a certain brightness is the same shade of black, an HDR TV’s display range goes further, allowing you to tell the difference between something that’s really really dark, and something that’s just dark. (Go put on a horror movie and you’ll be able to tell the difference immediately.)

For example, a wide shot of a campfire at night could have subtle details in the flame rather than appearing ‘blown out’, along with palpable definition to objects that are barely lit in the gloomy surroundings at the edge of the frame.

As Panasonic’s training manager Michael Price says, “It’s about control, not just extra brightness and results in more natural expressions of light and shadow.”

When we caught up with Hollywood cinematographer Vanja Cernjul he was positively brimming with excitement about HDR, saying that: “The whole composition is affected by the increased detail in brightness.

“You no longer have to choose whether to expose for the highlights or the shadows, so when I shoot I try and include a light source in the shot, which I can play within the HDR grading session.”

In post-production Cernjul will tinker with the levels of exposure, brightness, contrast and colour saturation, making them look as good as possible on an HDR-compatible screen.
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He thinks that filmmakers will, like him, be attracted to work on TV with the possibilities of HDR. Having just completed shooting the second season of Marco Polo in HDR, Cernjul sees streaming services as the natural home for HDR production, because of the number of original shows being commissioned by the likes of Netflix and Amazon.

HDR is bringing media closer to what the human eye sees, and by doing so, is creating more realistic images, from scenes bleached with sunlight to nighttime shots on city streets.

Here’s the big takeaway: HDR TVs and content will display a more realistic color range, with an expanded contrast ratio to make black parts of the image look closer to ‘true’ black.
So what’s HDR like to watch?

Watch some carefully crafted HDR, like Cernjul’s short showcase movie, Converging Beams, made for Panasonic, and you can see the potential. You get so accustomed to simultaneously seeing shadow detail and details in the highlights that you may come to find watching standard images a bit flat and dissatisfying.

Not only that, but HDR has some extra zip to it compared with standard viewing. There’s a new level of dynamism to images, something hugely evident in a film like the Lego Movie.

When we went from standard definition to HD, screen sizes were a lot smaller and just having the extra pixels was enough to transform the picture. Now that screens are so much bigger, however, it’s not enough to simply add more pixels, as there are other aspects of the image that can be improved.

What HDR adds in terms of additional colours, better clarity in shadows and highlights, is subtle but significant – and it delivers a much more visually satisfying picture than simply having extra pixels. The overall effect is a punchiness that’s tantamount to creating a 3D image.

But the tech still needs to catch up to the promise. Some cheaper LCD HDR screens struggle with displaying bright objects against sharply darker backgrounds, causing streaks of light to run down the screen or create halos around bright objects.

These issues are of less concern on the kind of OLED screens made by LG, Panasonic or Sony, where each pixel generates its own light and can go completely dark.

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