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60

PPI (Pixels Per Inch) settings are not used in web images. Images on the web, retina displays or otherwise, are displayed by their pixel dimensions (width and height) not any PPI/DPI setting. In fact, many web images such as png, gif, jpg may not even store a ppi setting in their internal data and rely on width and height settings. A 100 pixel x 100 pixel ...


23

The only definitive answer to this question is: Ask your vendor. Every vendor, every printer, every t-shirt maker, etc will have their own particular preferences as to how they want to receive files and how they want them set up. Discussing this with your vendor before you begin is crucial to ensure that the process goes smoothly. The general rules of ...


18

The PPI doesn't really matter if you use pixels as units; 1000x1000 pixels at 300 or 72ppi will still be 1000x1000 pixels. But when you change the units to inches, then you'll notice one is smaller than the other; there will be be more pixels per inch as the name says. As you mentioned, PPI is more for printing, but it can also now be used as a reference for ...


17

I've always thought DPI was somewhat of a misnomer... It really only applies if you are printing an image, otherwise, well, pixels are pixels. For an image on a site, well, it really doesn't matter, just get as many as possible, to fit the required size. Printers vary somewhat, but around 300 DPI is usually a good rule of thumb for anything around the size ...


14

A pixel (the word was originally coined, iirc, by IBM and derives from "picture element") is the smallest indivisible unit of information in a digital image. Pixels may be displayed, or they may be printed, but you can't divide pixels into smaller pieces to get more information. How many channels and bits per channel make up one pixel is the measure of how ...


11

The DPI of the image itself is not really that important. What is important is how big you will print the image and what kind of press/printer will be used to print it. This is why: DPI, dimensions and pixels The dimensions of an image can be specified in 2 different ways. Indicate DPI and dimensions in inches (or cm) Indicate dimensions in pixels (or ...


9

Illustrator doesn't have a setting to adjust the Actual Size view of print documents to a screen's pixel density. To 'calibrate', I helped myself by holding an A4 sheet against an A4 document on the screen and zooming until they matched. Then I – ahem – wrote down the zoom percentage on a super-sticky Post-it, which now adorns the frame of my screen… (The ...


8

You are talking about microprinting. The whole idea of that, is that you cannot reproduce it by using printers or printing presses. It is engraving that are designed to trip up professional counterfeiters. So, no, I can´t see how on earth it would be possible to pull off. (of course, if you have unlimited resources and good connections in shady parts of town ...


7

I recently read jrista's marvellous q&a from photo.stackexchange. While the question is titled "How do I generate high quality prints with an ink jet printer?" it covers DPI & PPI relationship to quite an extent and has real-world print examples. Current Q&A contents: Summary Detailed Explanation Empirical Studies: Does PPI really matter? ...


7

DPI (digital dots or pixels)/PPI defined: 300 dpi/ppi = 300 pixels used for every 1 inch line of ink coverage. 1000 pixels will yield a 3.3333 inch line @ 300 dpi of resolution DPI and PPI have been used interchangeably (though not always accurately) since pixels entered the printing industry. DPI comes from halftone/screen dots in offset printing. If a ...


7

If the printer is asking for 600dpi, it means [he] either didn't understand the question or there has been a failure to communicate. 600dpi (dots per inch) is the resolution at which your billboard will be printed. There was a time, in the Long Long Ago, when that would have been considered pretty high-resolution stuff -- I remember having posters printed ...


7

Should my images be saved at a specific PPI? No. iOS ignores PPI (pixels per inch) stored inside images. However, the pixel dimensions of your images do matter, so make sure you get those right. It’s also important to ensure your 2× images are exactly double the dimensions of your 1× images and that elements within the image are in the same ...


7

1: No. The printer will print the image using the most appropriate resolution it has at its disposal. This is why we have drivers. 2: Short answer, yes. Long answer, it depends. Depending on how the printer software uses the word "quality", the printer may use more or less ink. In some cases, a "draft" quality will use less ink (and produce a lower quality ...


6

iPhone4 retina displays are 960x640 with 326 dpi (ppi). http://en.wikipedia.org/wiki/Retina_display#Display


6

Did you change the pixel dimensions as well? DPI is typically meta-information to tell a printer how large to print the image. It normally doesn't have any affect on the actual pixel dimensions of the image. If that's the case, than the difference is likely that you saved the image with a high JPG compression setting. The best way for us to determine ...


6

How close are you going to view the 4' canvas? Is reducing the dpi really going to adversely affect printing on a coarse material like cotton or silk. Thats coarse relative to smooth glossy photo prints, for example. See this recent question: What DPI should a large format artwork for print be done at?


6

If you'll be going to a digital print shop to make the posters (which would be usual for a small run for a local event), you'll be fine at 150 ppi, and for a background image you probably wouldn't be in trouble at 100 ppi, particularly since it likely won't contain a lot of high-frequency detail that would conflict with your text. An 11x17 poster is mostly ...


5

Specifically on PPI for web or other on-screen images: 72PPI (or 75, or 96) is a myth. Yes, there is a figure which applications use to decide how many pixels to use to render fonts specified in points, but this hasn't got any relevance to images, other than: if your Photoshop document is 72ppi, it doesn't matter if your font units are set to points or ...


5

ppi = pixels per inch = typically used as a measurement for screens (the iPhone 4 has twice the ppi as the iphone 3) dpi = dots per inch = typically used as a print measurement and refers to the number of pixels in the image that will be used to render 1" on paper scaling = this is a loaded term and why the answer isn't simple. For raster images, you can ...


5

Modified Modified Huffman. It's a method of fax compression.


5

While PPI definitely doesn't matter — it's pixel dimensions that matter for web and app design, you should be very careful about using design applications and mixing PPI settings. Here's why: However, if you plan to use Photoshop and different pixel densities for each document, dragging layers and copying layer styles between documents scales layer ...


5

85cm x 200cm is 33.4646in x 78.7402in. To set it at 700ppi (pixels per inch) you need to multiply that by 700, so your document should be: 23425px x 55118px, independent of whatever ppi you choose in Illustrator. That is a LOT of pixels, particularly because illustrator outputs a vector file that is 100% scalable (unless you are using raster images within). ...


5

John answered if you are concerned about raster images within Illustrator. However, I wanted to point out that Illustrator - being a vector based application - is resolution independent. This means there is no ppi/dpi setting. Vector content has no ppi/dpi it scales infinitely without issue. PPI/DPI is for raster-based images where scaling can vastly alter ...


5

Other answers have more than adequately explained resolution, so I'll explain density, which has a VERY different meaning in the graphic design world. Ink density is the total area coverage of paper by the printed ink dots, from 0-400% (100% each for CMYK), and this is important because depending on the printing process, only 250-350% is available for use, ...


5

It depends on how close you expect the viewer to stand, as vision is based on angular frequency. If your image has a certain size and you need to print it at some size then there is not much you can do about the resolution. 150 PPI is usually quite acceptable for items you view at a distance. Most human sized outdoor commercials are at that kind of ...


4

You can use the build in Preflight function. [I don't know when it has been introduced but its there in Acroboat 9 Pro and above] Advanced > Preflight [Keyboard Shortcut Shift + Ctrl + X ] Have a look at this video to see what I mean: http://www.mattbeals.com/videos/Adobe/ShowImageRes/ShowImageRes.html There are also other plugins and stuff, but as ...


4

If you want your photoshop to match the pixels on the Kindle, then your PSD file should be 1024x600 pixels. DPI is a measurement of the pixel density on the device itself and has no real bearing on your PSD file.


4

Roger's right. You WILL NOT be in trouble at 150 ppi for an inkjet-type print process, especially at that size. But let's pretend that you can't change the 300 ppi requirement. The problem you are running into is memory, and it may be an impossible hill to climb without upgrading your hardware, but here are some basic steps that can mitigate the problem: ...


4

PPI means "pixels per inch," and is a web display measurement. DPI means "dots per inch," and is a print measurement. If your Image Size dialog box reads "300 pixels per inch," you're fine. However, if you're starting at less than that, most likely you cannot arbitrarily make the PPI larger without sacrificing quality. (Depends on how far you're sampling ...


4

It depends on the usage the final file will be put to. If it's for web, definite dimensions could be similar or proportionately higher (never lower) to the dimensions expected to be shown in the final webpage (it can then exported in required dimensions using "Save for Web" functionality. If it's for print, it will again depend upon the quality of the ...



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