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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 ...


21

A pixel is a pixel is a pixel. Resolution (as in PPI/DPI) is meaningless* in a digital context, the only time it is meaningful is when you are printing (or otherwise transferring to a physical medium) your image. A 100 × 100 pixel image saved at 72PPI will show on your screen exactly the same as the same as a 100 × 100 pixel image saved ...


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 ...


16

On a normal monitor imaging element is in a square matrix. We then call the aspect ratio of that pixel 1. Aspect ratio is just the width/height. A aspect ratio of 1 is a square and a aspect of 16/9 is elongated. In the case of monitors we have 2 separate aspect ratios the ratio of the monitor and the shape of each pixel, called pixel aspect ratio. These two ...


15

320 x 480 is a very common resolution for mobile phones. Here is a big list of a lot of phones and their resolutions. Maybe it'll help give you an idea of what's out there. For desktops Full Screen: 800 x 600 1024 x 768 1280 x 960 1280 x 1024 1600 x 1200 Widescreen: 1280 x 720 1280 x 800 1440 x 900 1680 x 1050 1920 x 1080 1920 x 1200 1024 x 768, 1280 ...


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 ...


12

Not exactly, but... ... there is a way to achieve the effect you describe. Apparently you can change the scaling mode for smart objects, but it's a global setting that takes effect for newly created Smart Objects: Preferences > General > Image Interpolation. So the procedure is like this: Open your background image Set Preferences > General > Image ...


12

Millimeters, inches, centimeters, picas.. all do not translate universally to pixel sizes. Pixels are not a physical object, there's no measured size for a pixel. Physical measurements only relate to printed materials, never anything on screen. You need to ask your client if a pixel size is acceptable. Perhaps show him/her what 71mm would be at 72ppi (...


11

Designing a graphics for a header is not just designing the image, but knowing how the header will look overall. If you provide only the image, there is a chance the other person making the website put just a tini little version, or a deformed one for example. So the first step is to prepare a canvas simulating diferent screen devices, let's say: 1920 width,...


11

No this is not possible. To be entirely sure I went through every option that the layer has. A workaround might be setting up guides with the size you want the pixels to be and then using the Pencil tool to fill them.


11

No. I'd approach it one of these two ways: Use a multiplier for your pixel brush size, and just use nearest neighbour interpolation to resize your image to the correct size without deforming it. (let's say you had to blow up your pixel art 10x, just use a 10px square brush). You can always have a second view zoommed out to simulate the final size. ...


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

In general, enlarge the image using Bicubic interpolation (sometimes, depending on the image, "Bicubic Smoother" works better, but usually straight Bicubic is more satisfactory), then either use Smart Sharpen to bring back the edge contrast, or copy the layer, set the blend mode of the copy to Overlay, and run Filter > Other > High Pass. Sometimes you ...


9

Preview is simply a terrible PDF viewer. It has many rendering issues with PDFs. Preview is designed by Apple to view PDFs for average home end-users. It is not designed to be a professional PDF viewer. Apple simply appears to not be concerned with many rendering issues in Preview where PDFs are concerned. What you are describing I'd actually call one of ...


9

Nothing wrong, is just the Indesign Typical Display Image. Select the image > Go to menu Object > Display Performance > High Quality Display The Typical Display Image is to work faster with the application, having a book with many images and all at High Quality Display would reduce the work speed.


8

Well, where I come from 400x600cm is 4x6 meters. :-) 30 dpi for final output is more than enough for a billboard of that size. It's not unusual for final output to be 12-15 dpi in this context. The usual professional billboard workflow in Photoshop is to build the image at a small scale with high ppi (e.g., 4x6cm @ 300 ppi), but in this case you can work ...


8

For our printing partners, we almost exclusively submit PDFs for printing. Unfortunately, PDFs have dimension limits. It was around 5 meters (I Googled, it's 200 inches). So we scale down. We usually do it for those hoarding artworks -- hoardings are "panels" that you use to board up when you're constructing a new store inside a mall (or any building ...


8

As I've previously said here and here... 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 ...


7

Solution number 1: Draw a Marquee selection around the element; choose Edit → Copy Merged File → New; hit Return; “Paste.” now you have your element ready to be saved in png format Solution number 2: right click on the layer (or group of layers) choose to duplicate the layer (or group) choose New as a destination and you get a new document with your ...


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

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

Photoshop does not treat 1px = 1 pt. Except at a specific situation. This is when the image is set to 72 ppi + you are using pt as a unit + you have the point/pica set to 72 pt/inch. The explanation is that if you set the ppi to 72, it matches the idea that you can have 72 points on each inch. You can see this in action changing this values in Photoshop (...


6

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


6

I think Jan Steinman was close with his angular explanation. The DPI table is good as well but in the end it all comes down to pixels not DPI for photographic images. Forget DPI, a good rule of thumb is that across your field of view your eye can not see more than 8,000 pixels. Therefore you should not create a bitmap image of more than 8,000 pixels across. ...


6

This is answer is purely from a website standpoint. Media querie, curtesy of CSS3, gives us more control over how a website will look at various resolutions. As you scale down the width of the browser it will swap to the code for that width. Some info on Media Queries - http://www.stuffandnonsense.co.uk/blog/about/hardboiled_css3_media_queries This falls ...


6

The type of the display is not actually important. Any decent OS has options to set the screen resolution and/or font, icon and other GUI elements sizes. Here is simple example: It has been taken on my netbook with OpenSuse and 1024x600 display, far away from "retina display". I simply set the default UI font to DejaVu Sans 24 and switched on all "anti ...


6

While you can increase text size etc to magnify things before taking a screenshot Another option to try (on MacOSX) is to use the disability features to zoom the screen in before taking a screenshot. I haven't used a mac for over a year but I remember in 10.5 you could zoom in quite a lot and I think it stayed quite clear. I'm sure similar features are ...


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