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Dell is selling a laptop (Studio 15) where the options for screen resolution are 720p, 900p, and 1080p. What do they mean?

I've found a Wikipedia entry that lists the old confusing (UXGA, WUXGA, &c) names and seems to indicate that 1080p might be 1920x1080. It has no information on 900p or 720p.

Really, it was bad enough with the WUXGA style descriptions. I think vendors should tell you what they're selling. If you know what the screen resolutions are, I'd appreciate hearing it here.

Hennes
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Brian
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    It's a right pet-peeve of mine when people use [xxx]p to tell me what resolution their monitor is. Monitors are not televisions, please stop treating them as such. – Phoshi Sep 19 '09 at 15:57
  • @Phoshi: I can treat my laptop as a TV and there is nothing you can do about that. `1080p24` simply means my laptop screen is ready to display content that is of 1920 pixels width and of 1080 pixels height in a progressive way at 24 frames per second. This should tell you enough when you are interested in the resolution of my laptop, it's not that a few pixels more are going to matter... – Tamara Wijsman Jan 08 '12 at 02:09
  • @TomWijsman: And that's the reason why the average laptop resolution has actually shrunk, because having a marketable 720p is more important than having a sane working resolution. – Phoshi Jan 09 '12 at 14:02
  • @Phoshi: I can work sanely on my laptop just fine. If you although go for a smaller screen, you should crank up the DPI of your system as well the zooming level of individual applications. However, on the general laptop that's not a necessity... – Tamara Wijsman Jan 09 '12 at 20:45
  • @TomWijsman: Sure, and I can work on smaller and wider resolutions, but that doesn't mean that 720p makes more sense than the resolutions that came before it! – Phoshi Jan 11 '12 at 13:31
  • @TomWijsman The lower unit cost due to economies of scale of manufacturing TV screens has forced laptop manufacturers to move to 16:9 aspect ratio over the last three years or so, with only Apple buying in the quantities to allow it to stick with 16:10. – paradroid May 18 '15 at 21:58
  • @Phoshi: That is only the case if you want to work on smaller and wider resolutions. – Tamara Wijsman May 18 '15 at 22:26
  • @paradroid: Was the chicken first or the egg? You choose it the way you want to see it. – Tamara Wijsman May 18 '15 at 22:27
  • @TomWijsman It's actually a known fact. There was a lot of discussion about it when Lenovo moved ThinkPads from 16:10 to 16:9 screens, three generations ago, with a lot of people being very unhappy about it. Shortage of high-resolution 16:10 screens for certain models, making them hard to get hold of, forced the change. – paradroid May 19 '15 at 00:07
  • @paradroid: Uhm, no, it is not a fact. A statement concerning one manufacturer yielded from a discussion does not imply a fact concerning all manufacturers. Furthermore, a statement concerning screens for certain models does not imply a fact concerning screens for all models. – Tamara Wijsman May 19 '15 at 21:40
  • @TomWijsman Anything is arguable if your standpoint is ignorance if facts. Loads of other links, I'm sure, but I'm on my phone at the moment. http://forwardthinking.pcmag.com/displays/283041-where-displays-are-heading – paradroid May 19 '15 at 21:56
  • I'll find a much more un depth explanation from Arstechnica or Anandtech that I can remember, but can't find at the moment. – paradroid May 19 '15 at 22:04
  • @paradroid Magazines are not sources of facts. Please refer to original verifiable resources. It's not a fact until you demonstrate it to be one. – Tamara Wijsman May 19 '15 at 22:22
  • @TomWijsman LOL okay, so if a journalist reporting on a conference for display manufacturers, or articles from the most renowned hardware sites on the internet are not enough, what sort of evidence do you want? I know it's good to be sceptical of dubious sources, but.... heh – paradroid May 19 '15 at 22:29
  • @paradroid: No, journalists are not verifiable as they write the most misleading titles reflecting their own viewpoint. A verifiable source cannot be misleading or based on a viewpoint, because it must be the actual source of your fact. For your fact, a verifiable source would be multiple screen producers and manufacturers making statements about 16:9 being forced. They are the only ones that can feel forced to do this and therefore they are the only ones who could make it a fact. This fact is not brought to existence by the most renowned economists, predictors, statisticians or journalists. – Tamara Wijsman May 19 '15 at 23:38
  • @paradroid: For example, your PCMag article references the DisplaySearch firm which does research and consulting. They label themselves analysis experts that make predictions and reveal trends. Predictions and trends aren't observations. However, DisplaySearch is not a part of that industry. They are not the "laptop manufacturers" that make the actual choices based on their reasoning. Therefore DisplaySearch cannot state it as a fact that laptop manufacturers did it because they were forced to; all they can do is assume and have it spread as a misleading story that makes u assume it as a fact. – Tamara Wijsman May 19 '15 at 23:47

6 Answers6

25
  • 1080p is 1920x1080
  • 900p is 1600x900
  • 720p is 1280x720
Tamara Wijsman
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ctzdev
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    always, for all things too. – Xeoncross Mar 13 '10 at 00:47
  • Your 900p horizontal resolution is wrong. The aspect ratio for widescreen is 16:9, 900p should be 1600x900. [See table](http://en.wikipedia.org/wiki/Computer_display_standard#Standards). – bobobobo Jan 08 '12 at 00:55
  • @bobobobo: Indeed, he actually copied this of a forum somewhere. o_O – Tamara Wijsman Jan 08 '12 at 02:12
  • so the greater the pixels the better the view as far as i have seen, why is that so? – 168335 Jan 08 '12 at 02:19
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    @168335: You can't show a human face in a single dot. If you had 100 dots, you would have a very very pixelated face. If you have a 1000 dots, you have a blurred face. Now imagine having 2073600 dots to see that face, [yeah baby](http://www.mutluduvar.com/var/albums/Sweet-Babys-/baby-face-desktop-wallpaper.jpg?m=1294525962)! Requires a Full HD monitor, although you even get the point on lower resolutions... – Tamara Wijsman Jan 09 '12 at 20:50
  • Pretty much everyone's answer is assuming that the pixels are a square shape, when 1080p does not have to use square pixels to make a 16:9 display. Before Full HD was common (which requires 1920x1080 pixels) it was fairly common to have 1440x1080 with rectangular pixels that were wider than they were tall to make the correct 16:9 physical screen with fewer cheaper pixels and still be able to advertise the screen as 1080p. This used to annoy me incredibly and I'm still upset at having to dig down to find out the actual specs. Hence the ancient Q revival. – BeowulfNode42 Jul 11 '16 at 14:16
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The shorthand format for resolution in screen or camera taking - a number followed by p, or a number followed by i, means p - the "progressive" digital film format or i - the "interlaced" digital film format.

The number that goes before i or p simply means one of the two lines of dots that make up the resolution - it is always the vertical or side line given. And that is going to be 1080 dots (pixels) exactly with 1080p.

What this shorthand resolution format doesn't tell you is the number of dots in the horizontal line of pixels. It can be any number.

1920 is the most common value for the number of horizontal pixels these days in 1080p resolutions - it is the standard "Full H.D." format, found in Blu-Ray discs and also produced now for most 1080p home T.V. sets. That resolution is 1920 x 1080. But that is not a definition of what 1080p is, though 1080p can be and is that. 1080p is also 1440 x 1080 pixels in progressive digital film formation.

Progressive means each frame of the film taken (each still photo it is in progressive format) is a full frame of the full number of resolution pixels - i.e. 1920 x 1080 films show every single frame made up differently, separately with that number of pixels, and the frames just progress in sequence, with nothing to smoothen them nor any pixels cut out in order that less memory is used. A film can be shot in any value of frames per second - whatever value they may be shot in, cinema films are usually edited to be released in 24 frames per second. So there are 24 full value frames of 1920 x 1080 pixels every second with that 1080p resolution. Typical home camcorder frames per second are 30 fps and 60 fps for rapid motion filming.

Interlaced is the other digital film format. Not all pixels are used in each frame. A frame is usually broken into fields, a number of fields make up a frame. Usually there are significantly less frames per second than with the progressive format, but as each frame is made up of a number of fields, this is also high quality, high definition digital film. Each field is not taken (or transmitted / played back if talking about T.V. sets which give i signals) with the full number of available pixels - different parts of the full frame will be taken in different frame, depending on motion and other variables (the machines work so quickly). The fields are played back rapidly, making each frame advance, to kind of give the effect of the whole resolution being used - as it is acutually (usually), but just not all at the one time. i film often looks more 'dancy' or slightly jerky to 'p' film.

Most of the world grew up for decades watching i - interlaced - film, which was also the most popular analogue format in standard definition, for beaming film to TV sets in homes. Now the world is slowly switching to transmitting tv in p - progressive format. (Some places have had progressive TV signals available to receive for many years, though). I think i is still most commonly found, if you look all around the world.

Perhaps I understand a little bit why some people are reluctant to associate the screen resolutions which they see TVs have with their laptops and laptops generally. But I guess that is only not being used to it, and also it's a big product of market programming - all those boxes with 1920 x 1080s and 1280 x 768s or whatever - it's almost natural to want to set those quite annoying things aside to "the world of the new TVs" which have come upon us. I guess it annoys people even with TVs - 12 or 13 years ago you'd have to search all day or longer to find an advert for a Television - the very idea of it was weird, now it seems to be more a part of life than work or hobbies or spending time with the children. And it's natural to want to sideline it only to those big boxes with the new TVs that we didn't have growing up.

But actually, those boxes contain more or less the same thing as a laptop screen in the modern day. Some digitals screens are set to TV use only, some to computer monitor use only, and some to both. But, essentially, they're virtually the same digital item - whether on a laptop or in one of those big HD TV boxes in a store. It's natural that you want to know the resolution of your laptop screen. Your laptop screen is made up of dots - that's all - and most people are aware by now, how many there are is usually the biggest factor in how good it is to look at. If you play DVDs on your laptop you'll want to know (though it's not so relevant for that, unless you have a 17 inch laptop and an DVD upscaling laptop, if there are any, I don't know). For your home movies shot on HD home camcorders which are inexpensive these days, then your laptop resolution really does matter.

The only thing is - your laptop is very unlikely indeed to be anything more than the standard resolution for the size of the screen, nearly all NEW (new = edit addition, sorry for any confusion) laptops are the same for each size of screen in inches (released within a year or two of each other, that is) - so yes, that's a reason why it's a bit annoying to see the figures for screen resolution for laptops all of the time. But, with a really budget end laptop, it could be a little less than the modern standard resolution for the size (in inches) of screen.

user31027
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  • 720p is 1366x768
    • HD (High Definition) - approx 16:9
    • (HDTV is 1280x720, yet both were marketed as 720p instead of laptop's 768p, films are actually 768p and yet your HDTV can still visualise them)
  • 900p is 1600x900
    • HD+ (High Definition Plus) - 16:9
  • 1080p is 1920x1080
    • FulHD (Full High Definition) - 16:9
  • 4K is 4096x2160
    • 4K (The current standard, as of 2012, in digital cinema) - 1.8962:1
  • 2880p is 5120x2880
    • 5K (Retina 5K Display) - 16:9
  • 8K UHD is 7680x4320
    • 8K (Ultra-high-definition/Super Hi-Vision) - 16:9
xchiltonx
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The "p" format (1080p, 900p, 720p) come from HD. These are widescreen display formats (always) having an aspect ratio of 16:9.

The number they give you before p (eg 1080) is the height resolution. Multiply by 16 then divide by 9 to get the WIDTH (1080*16/9 = 1920).

So:

  • 1080p is 1920x1080
  • 900p is 1600x900
  • 720p is 1280x720 (but usually these are actually 1366x768. Not sure why).
bobobobo
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Wikipedia has a listing @ http://en.wikipedia.org/wiki/File:Vector_Video_Standards2.svg

720p refers to the pixel count - 1280 pixels x 720 pixels - and is one of the HD formats. The number before the 'p' is usually the second number. I have not heard of 900p with respect to HD formats but if you were to trust the Wikipedia link above, then my guess would be that the screen resolution is 1440 x 900.

gronostaj
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sunraa
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Some caveats to the above: HD video is shot (and played back) at 1920x1080 resolution. Most digital "film" shoots (using professional cameras such as the RED or ARRI) are done at 2K resolution, meaning 2048x1080p. Few higher-end digital cameras are limited to 1920x1080 resolution, so image editing could be tricky. Also, be aware that a screen with only 1920x1080 pixels has no extra room for borders, video controls, toolbars, skins, etc. To see anything at full resolution, it must be displayed in "full screen" mode only. So I would NEVER buy a computer display with only 1080 vertical pixels or only 1920 horizontal pixels.

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    comment from [John](http://superuser.com/users/40549/john): Well Thomas you're a bit limited. After 1920 x 1080 there's not that much to choose from. I have a 1920 x 1200 LCD monitor, but after that, (and there are higher resolutions) monitors get MUCH more expensive, like 1,000+ But if you want to pay that much you can get bigger than 1080p, but normally 1080p is the market limit as far as price/size ratio goes. – quack quixote Jun 20 '10 at 23:42
  • +1 on the above comment, especially since the asker is referring to a *laptop*. – Torben Gundtofte-Bruun Aug 04 '10 at 11:21