SDTV, HDTV and 4KTV: TV resolutions explained

Whether you’re in the market for a new TV or just want to keep up with TV technology trends, you’ve likely come across SDTV, HDTV and, more recently, 4KTV. What exactly is the difference between them? This article will explain what separates SDTV from HDTV and HDTV from 4KTV, including picture, price and even recommendations for how far to sit from the TV.

Resolution is all about the pixels (basically)shutterstock_511626514

If you look very closely at your TV, you can see tiny dots of color. These dots, known as pixels, collectively make up your TV picture. More pixels result in sharper images and more fluid movements.

Pixels are arranged in lines, and the number of pixel lines greatly determines the resolution classification, but it isn’t the only factor. How the image is loaded can affect picture quality as well.

The lowercase “i” or “p” in a TV resolution is in reference to how the lines are loaded onto the screen.

Interlaced (i)—Interlaced means that half the lines refresh with each new frame. So, lines 1, 3, 5, etc. of the frame would load first followed by lines 2, 4, 6, etc.

Progressive (p)—Progressive means that all the lines of the frame are loaded simultaneously. This results in a better quality picture, especially in scenes with fast movements.

So, whether your picture is SDTV, HDTV or 4KTV depends on the number of pixel lines. From there, the “I” or “p” indicates how those pixel lines load. Here’s how each TV type stacks up.

What is standard definition TV?

TV resolutions of 480i or 480p are considered standard definition. In these resolutions, the pixels are arranged 640 x 480. With this minimal number of pixels, images are less defined and appear “pixelated” (meaning you can see the individual pixels) the closer you get to the TV.

What is high definition TV?

TV resolutions of 720p, 1080i or 1080p are considered high definition. In 720p, the pixels are arranged 1280 x 720. This is a lower-quality HD picture, known as “HD Ready.” In 1080i and 1080p, the pixels are arranged 1920 x 1080. The higher number of pixels in 1080 results in a better picture, known as “Full HD.”

What is 4KTV?

TV resolutions known as 4K are the among the best currently available. Pixels are arranged 3840 x 2160, similar to the movie theater resolution 4096 x 2160. The “4096” aspect is where “4K” gets its name. The number of pixels in 4K is four times that of Full HD, and many more times that of SD, resulting in a near-perfect image, known as “Ultra-HD.”

What are the price differences for each?

As you can expect, the TVs with a better picture quality will come with a higher price tag, especially those with larger screens. 4KTV prices have come down considerably in recent months, but they will still typically cost you more than a 1080 resolution TV.

As HD televisions have become more affordable, they have replaced SD as the new “standard”. Consequently, SDTVs may be hard to find at your local electronics store. If you do find one, however, expect to pay less for it than you would an HDTV.

Does having an HDTV mean everything I watch will be in HD?

Not necessarily. Your HDTV is simply capable of displaying images in HD resolution. It’s up to your TV provider and the networks to offer programming in SD, HD or 4K resolution. If you have an HDTV, but the show you’re watching is in SD, your picture will be in SD.

It is for this reason that many are still preferring HDTVs over 4KTVs. Though more 4K content is becoming available, most programs are still shown in HD. As more programming becomes available in 4K resolution, 4KTVs will likely gain in popularity. For now, 4KTVs are best for some movies, select shows on streaming apps, new gaming consoles, and photography.

How far should I sit from the TV for the best picture with each?

The better your TV resolution, the closer you can get to the TV without compromising picture quality. For SD pictures, you’ll want to sit roughly three times the height of your screen away. For example, if your TV is 42 inches high, you’ll want to sit about 10.5 feet away.

For HDTVs, most viewers can sit about 2 times farther away than your TV screen height. 4KTVs allow you to get even closer, around 1.5 times your screen height without compromising picture quality. Sitting closer will give you a more immersive viewing experience. Of course, you should always sit wherever is most comfortable for you.

In conclusion: SD is on its way out, 4K likely here to stay

SDTVs have largely given way to HDTVs. As 4KTVs become more affordable and more 4K content becomes available, we will likely see a similar trend with 4K resolution replacing HD. If you’re shopping for a new TV, consider resolution quality – you may find that spending a little extra money on a higher resolution TV to be worth it!