Dpi vs ppi for retina display?
Pixel Density
Like dpi (dots per inch) used in print publishing, ppi (pixels per inch) is a measure of image resolution.
The higher number, the greater the detail.
The increased pixel densities of Retina displays on modern iPads, iPhones, MacBooks, and other Apple divices allow for super crisp, high resolution imagery.
On Retina, individual pixels are indistinguishable to the naked eye.
Not only is image quality better, but text is sharper, video playback cleaner, and the overall experience at normal viewing distance is more enjoyable.
In the context of MagCast and digital magazine publishing, digital magazines can look fantastic in Retina, but let's look at how to make sure of that.
The 9th generation iPad display is 2160 x 1620 pixels at 264 pixels per inch (ppi).
As a point of comparison, the 27" monitor this article is being written on, at 1920 x 1080, is around 85 ppi.
Optimizing images, for web work anyway, often involves minimizing the image file size while maintaining image quality. And that makes sense on the web, where storage and bandwidth costs can add up, and download speeds matter.
If you take your typical 72 ppi web image and use it in your magazine design, the result can be less than ideal, so go with higher res images.
For digital magazines, published via the MagCast platform, flip that optimization notion on its head.
"Go big or go home!"
WAIT, before you take that to another magazine app publishing platform, hold the phone.
MagCast is unique in that we never charge for storage or bandwidth, and have nearly 300 download nodes on six continents, so the large file sizes of high reolution images does not add to your overhead, nor slow down your magazine.
That's not true on most other platforms.
On another platform, a beautiful magazine full of big, crystal clear, high resolution photographs, would be a more expensive proposition, and could make for a slower app.
When you're working with MagCast though, you can tell your design team, "Just make it beautiful," because perfection will never cost you a penny more.
