Comments on: Myth: 72dpi for Web Images http://technicallyeasy.net/2007/07/myth-72dpi-for-web-images/ Making technology easier to understand. Sat, 11 Feb 2012 13:19:27 +0000 hourly 1 http://wordpress.org/?v=3.3.1 By: Paul Salmonhttp://technicallyeasy.net/2007/07/myth-72dpi-for-web-images/#comment-31989 Paul Salmon Tue, 05 Apr 2011 12:29:53 +0000 http://technicallyeasy.net/2007/07/myth-72dpi-for-web-images.html#comment-31989 Thanks for the explanation, Ian. Thanks for the explanation, Ian.

]]> By: Ian Garretthttp://technicallyeasy.net/2007/07/myth-72dpi-for-web-images/#comment-31986 Ian Garrett Mon, 04 Apr 2011 22:09:03 +0000 http://technicallyeasy.net/2007/07/myth-72dpi-for-web-images.html#comment-31986 The 72 comes from typography and points, which are 1/72 of an inch. So 72 points, or dots, would be an inch of dots. It was to correlate the size of the font on screen to the size of the font on the printed page and older displays were designed to work with the 72 ppi size to make the screen to print transition easier.It is now fairly meaningless in terms of real size, and just refers to a logical size for that transition and is even more about font reproduction than images now. They end up next to each other a lot so hypothetically, this logical size would mean that if you were to have a 12pt font, it would appear to be 1/6 of an inch tall (1 pica) and so it was that a "72 dpi" image next to it would have the same appearance on you screen as when you printed it out.This means nothing anymore though. Just persistent conventions of digital typography printing conversions. The 72 comes from typography and points, which are 1/72 of an inch. So 72 points, or dots, would be an inch of dots. It was to correlate the size of the font on screen to the size of the font on the printed page and older displays were designed to work with the 72 ppi size to make the screen to print transition easier.

It is now fairly meaningless in terms of real size, and just refers to a logical size for that transition and is even more about font reproduction than images now. They end up next to each other a lot so hypothetically, this logical size would mean that if you were to have a 12pt font, it would appear to be 1/6 of an inch tall (1 pica) and so it was that a “72 dpi” image next to it would have the same appearance on you screen as when you printed it out.

This means nothing anymore though. Just persistent conventions of digital typography printing conversions.

]]> By: Paul Salmonhttp://technicallyeasy.net/2007/07/myth-72dpi-for-web-images/#comment-30174 Paul Salmon Mon, 06 Sep 2010 19:46:56 +0000 http://technicallyeasy.net/2007/07/myth-72dpi-for-web-images.html#comment-30174 In reality, a 72 dpi image that is 300x300 pixels will look exactly the same as a 300 dpi image that is also 300x300 pixels. The reason? DPI has absolutely zero effect on images that are displayed on a monitor. In reality, a 72 dpi image that is 300×300 pixels will look exactly the same as a 300 dpi image that is also 300×300 pixels. The reason? DPI has absolutely zero effect on images that are displayed on a monitor.

]]> By: swaghttp://technicallyeasy.net/2007/07/myth-72dpi-for-web-images/#comment-30172 swag Mon, 06 Sep 2010 18:23:21 +0000 http://technicallyeasy.net/2007/07/myth-72dpi-for-web-images.html#comment-30172 72 dpi for web images is mentioned in those tutorials for good reason. back in the day of dialup and stingy storage alotments, the 72 dpi was recommended because the standard 4:3 crt monitor was pretty much incapable of displaying greater image resolutions than 72 dpi. I'm unsure as to who decided that would be the cut-off point, but in a world of web design greater dpi was needless weight added to the file size. 72dpi at whatever size was more compact and just as clear as a 300dpi image of the same size. It was (and still is) about economy and low bandwidth. 72 dpi for web images is mentioned in those tutorials for good reason.
back in the day of dialup and stingy storage alotments, the 72 dpi was recommended because the standard 4:3 crt monitor was pretty much incapable of displaying greater image resolutions than 72 dpi. I’m unsure as to who decided that would be the cut-off point, but in a world of web design greater dpi was needless weight added to the file size. 72dpi at whatever size was more compact and just as clear as a 300dpi image of the same size. It was (and still is) about economy and low bandwidth.

]]> By: Paulhttp://technicallyeasy.net/2007/07/myth-72dpi-for-web-images/#comment-8442 Paul Fri, 11 Dec 2009 02:49:39 +0000 http://technicallyeasy.net/2007/07/myth-72dpi-for-web-images.html#comment-8442 There is a huge difference only when printed. When displayed on a monitor, PPI means nothing. The number of pixels, regardless of how many per inch is everything. The reason is simple. Say you have a 20" monitor. That would mean a resolution of about 1440x900 is 72 ppi. Many 20" monitors aren't that resolution, meaning they can have a higher or lower resolution, meaning that there are more or less than 72 ppi.So on monitors, there is absolutely no difference between a 300 ppi or 10 ppi image if they both have the same number of pixels. There is a huge difference only when printed. When displayed on a monitor, PPI means nothing. The number of pixels, regardless of how many per inch is everything. The reason is simple. Say you have a 20″ monitor. That would mean a resolution of about 1440×900 is 72 ppi. Many 20″ monitors aren’t that resolution, meaning they can have a higher or lower resolution, meaning that there are more or less than 72 ppi.

So on monitors, there is absolutely no difference between a 300 ppi or 10 ppi image if they both have the same number of pixels.

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