1 00:00:00,000 --> 00:00:05,000 Hey, did you know 4K often isn't actually 4K? 2 00:00:05,000 --> 00:00:12,000 What? Even though tons of electronics companies advertise screens, game consoles, and streaming sticks 3 00:00:12,000 --> 00:00:18,920 with 4K support, there's actually no real standard for what the heck 4K really means. 4 00:00:18,920 --> 00:00:27,960 It's just a word. It's just made up. You see, 4K is called 4K because it refers to resolutions that are approximately 4,000 5 00:00:27,960 --> 00:00:36,240 pixels across. The most common resolution that's advertised as 4K is 3,840 pixels horizontally by 2,160 6 00:00:36,240 --> 00:00:41,240 pixels vertically, which is what you typically see on TVs and computer monitors, often marketed 7 00:00:41,240 --> 00:00:44,560 as Ultra HD or UHD. 8 00:00:44,560 --> 00:00:50,560 And so this resolution isn't quite 4,000 pixels across, but the 4K used in movie production, 9 00:00:50,560 --> 00:00:55,800 called DCI 4K, measures 4,096 by 2,160. 10 00:00:55,800 --> 00:01:02,560 So the aspect ratio is about 1.9 to 1, a little wider than the typical 1.78 to 1 we're used 11 00:01:02,560 --> 00:01:09,280 to on TVs and your typical computer monitor. You might know that aspect ratio by its other name, 16x9. 12 00:01:09,280 --> 00:01:16,120 But DCI 4K isn't the only movie 4K, as it's primarily used for shooting the film. 13 00:01:16,120 --> 00:01:19,520 By the time you get to the movie theater, though, you're probably seeing the film in 14 00:01:19,520 --> 00:01:28,920 Cinemascope 4K. This sounds awfully fancy, but the actual resolution is only 4,096 by 1,716. 15 00:01:28,920 --> 00:01:35,840 And while that produces the 2.39 to 1 aspect ratio that looks cinematic, a typical 4K display 16 00:01:35,840 --> 00:01:40,280 at home has over one and a quarter million more pixels. 17 00:01:40,280 --> 00:01:43,840 So don't be fooled into thinking you're supposed to be seeing the latest blockbuster 18 00:01:43,840 --> 00:01:49,400 in some kind of mind-blowing detail, you're mostly just cutting off the top and bottom. 19 00:01:49,440 --> 00:01:54,360 To further illustrate this point, some products cut down resolution even further to get that 20 00:01:54,360 --> 00:02:02,520 cinematic, widescreen look. Sony's line of Xperia phones are known for this with their trademark Cinemawide 4K displays. 21 00:02:02,520 --> 00:02:07,720 But Cinemawide is actually just a cut down version of Garden Variety UHD, with a resolution 22 00:02:07,720 --> 00:02:15,360 of 3840x1644 to achieve a more theatrical 21x9 aspect ratio similar to many ultra-wide 23 00:02:15,360 --> 00:02:20,920 monitors. We're not trying to say these displays are bad, as they're still good looking OLED screens 24 00:02:20,920 --> 00:02:26,920 with HDR support, just don't expect more pixels than you'd get on a $300 TV. 25 00:02:26,920 --> 00:02:32,920 This illustrates why 2160p isn't an exact synonym for 4K, even though many people might 26 00:02:32,920 --> 00:02:38,080 want to call it that since we often refer to HD by its vertical resolution 1080p. 27 00:02:38,080 --> 00:02:43,280 We've already covered two resolutions marketed as 4K, with vertical resolutions falling 28 00:02:43,280 --> 00:02:47,680 well short of 2160 pixels, and on the other side of that coin, there are products like 29 00:02:47,680 --> 00:02:55,480 dashcams advertised as 4K because they're 2160p, but less than 3000 pixels across, producing 30 00:02:55,480 --> 00:03:01,640 a more square looking video that isn't really close to what we typically think of as 4K. 31 00:03:01,640 --> 00:03:06,960 So the use of terms like 1080p and 2160p to describe resolution actually go back to the 32 00:03:06,960 --> 00:03:13,640 age of CRT displays. We know those big, heavy TVs and monitors we used until the late 2000s and are still 33 00:03:13,640 --> 00:03:17,000 used today at really cool Super Smash Bros. tournaments. 34 00:03:17,000 --> 00:03:21,680 CRTs didn't have pixels in the sense that we think of them today, rather they generated 35 00:03:21,680 --> 00:03:27,520 horizontal lines that contained analog data, which varied as you went across the screen. 36 00:03:27,520 --> 00:03:31,840 In other words, they had a vertical resolution, but not a horizontal one. 37 00:03:31,840 --> 00:03:38,720 This is why the industry used terms like 480i or 576i to describe TV signals back when 38 00:03:38,800 --> 00:03:44,520 CRTs ruled the world, with the i standing for interlaced, meaning that a CRT would only 39 00:03:44,520 --> 00:03:48,320 scan half the lines of a frame at once to save bandwidth. 40 00:03:48,320 --> 00:03:55,240 By contrast, the P in 1080p stands for progressive, meaning the monitor scans the whole frame 41 00:03:55,240 --> 00:04:01,080 all at once. But even though modern LCD displays have a defined horizontal and vertical resolution, 42 00:04:01,080 --> 00:04:06,200 the practice of using a single 3 or 4 digit number to represent the entire resolution 43 00:04:06,200 --> 00:04:11,640 stuck around. But even if a product clearly states both its horizontal and vertical resolution, you 44 00:04:11,640 --> 00:04:16,320 really need both that information and the size of the display to get across how much 45 00:04:16,320 --> 00:04:21,080 detail it can convey, since a 4K resolution doesn't really mean much if you're sitting 46 00:04:21,080 --> 00:04:24,240 two feet away from a 200 inch screen. 47 00:04:24,240 --> 00:04:28,960 Which is why the 8K TVs on the market are mostly really big. 48 00:04:28,960 --> 00:04:34,520 So isn't there a better way than 2160p to describe how much detail a display can show? 49 00:04:34,640 --> 00:04:41,240 Yeah, it turns out that there is, indeed. It's a spec called pixels per inch, or PPI, which is just what it sounds like, the number 50 00:04:41,240 --> 00:04:47,840 of pixels in a one inch line. PPI, combined with aspect ratio, gives you a really good idea of what the actual visual 51 00:04:47,840 --> 00:04:53,360 experience will be like, and this system is used by none other than Apple, who uses it 52 00:04:53,360 --> 00:04:58,960 as the basis for the retina display marketing. Wow, they were actually right about something all along. 53 00:04:58,960 --> 00:05:02,880 Hey, that's the end of this video, thanks for watching guys, like it if you liked it, 54 00:05:02,920 --> 00:05:06,640 dislike it if you disliked it, check out our other videos, and comment below with video 55 00:05:06,640 --> 00:05:11,760 suggestions, and, oh, and, oh, and don't forget, oh, there's one more, and, oh, subscribe 56 00:05:11,760 --> 00:05:15,640 and follow, y'all, I see you almost forgot that part, don't forget.