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84

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 ...


37

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 ...


23

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 ...


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 ...


13

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 ...


11

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 ...


10

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 ...


9

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 ...


8

Because you are working with mm units, and the PPI uses imperial units. Because if you have exact mm you need to have halved pixels, which you can not, so the number is rounded to its nearest pixel count. Let me do some math for you. 2.5 / 2.54 = 0.984 inch. 0.984 inch x 300 ppi = 295.275 px.


7

Determining PPI Resolution given the Viewing Distance from the image For Raster (halftone screened) graphics, the PPI resolution is determined in two steps using only basic arithmetic. There's nothing mysterious. Step 1. Determine the necessary LPI (Lines Per Inch) A simple formula for the minimum acceptable LPI for viewing distance has been determined by ...


7

DPI is completely irrelevant. What matters is the number of pixels. A non-retina iPhone, for instance, is 320 pixels across. A retina iPhone is 640. (The iPhone 6's retina is 750 pixels wide). What makes a device 'retina' is that it uses more than one physical pixel to create a virtual pixel. An non-retina iPhone and an iPhone 5 are both 320 virtual ...


7

Could I suggest the "really, really obvious empirical method"? Get a sheet of A4. Hold it up to the screen. Change the image zoom scale until it matches. Forget DPI & pixel density. You just want it "the same apparent size". Unless you have a screen with a physical pixel density of 350 & at least 3840x2160, you cannot achieve a complete 1:1 image ...


6

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 ...


6

Printed medium works differently form screens. Screens have 3 color elements very close to each other. Each element is capable of different color intensities. Printers on the other hand produce dots of limited number of colors usually 4 colors, but can be more and have 3-4 mid tones or so. To show mid tones it has to spread the dots around. The end result is ...


6

Make sure that the screen definition as seen by Gimp is the real one: Edit>Preferences>Interface>Display>Monitor resolution (in 2.8: Edit>Preferences>Display>Monitor resolution). This part is the most often overlooked. If necessary, calibrate it(*). Make sure that the print definition (ie, the DPI for the printer) is correct: Image>...


5

Here's a full step-by-step (based on Adobe Acrobat Pro X): To quickly do it now Edit > Preflight (or shift & cmd/ctrl & x) Under 'PDF Analysis', select List page objects, grouped by type of object, then hit Analyze The results break your images out into handy ranges: Open these out, and you get a list of images. Clicking any takes you straight to ...


5

Every screen has it's own resolution. Or rather pixel density. Consider a 20" (diagonal) monitor: A monitor set to 2560x1600px has a ppi of about 137 A monitor set to 1920x1080px has a ppi of about 102 A monitor set to 1440x900px has a ppi of about 89 I post "about" because actual physical size of the monitor is a factor as well. A 20" monitor with a ...


5

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.


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

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 ...


5

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


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

To put it plainly, you can't. Or rather it doesn't work that way. An image has an existing number of pixels. When you increase the PPI without resampling, you tell that image to condense the same number of pixels into a "tighter" field. Thus reducing the image size. If you alter the PPI and use resample the application throws in all the extra pixels ...


5

are there times when the PPI flag is honored by iphone/retina/screen-density-aware software if it finds one? No. In fact, I can't think of any place it's really honored outside some very select software. For example, I believe, in Photoshop, if the PPI is set, it will affect the size the image is printed at, if you print directly from Photshop. But even ...


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

There is no such thing as a 300PPI image PPI is not an inherent property of an image. There is no such thing as a 300PPI image, or a 72PPI image. PPI is just a useful measurement for determining the print size of an image. Which means PPI is completely irrelevant unless accompanied by physical dimensions. If someone says "Can we have that image in 300PPI?" ...


5

Pixels have no size. Pixels are not a physical entity, they don't exist. You can't hold them, you can't touch them, you can't measure them. A pixel is merely the smallest increment your screen can display. The key words there are "your screen". The pixel size on a 1980 monitor will be different than the pixel size of a 2016 4K display. But they are both ...


5

When working on a project, its obviously important to use the right resolution Well, it's important to work at the correct size, although arguably not that important*. Work in vectors for anything and everything that isn't specifically an image, then resolution doesn't matter (vectors have no resolution). It's important to use the right resolution for ...


5

Don't use jpg or any raster format. Save as either a native .ai file, a .eps if transparency isn't an issue, or a .pdf file. All of these formats are best suited to save Illustrator artwork for print. There's really little to no reason to ever save an Illustrator file as a .jpg for printing.


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