When designing graphics for a universal app, what is the best DPI to use? In an ideal world we would all use gfx that are the same DPI as the screen (326 for iPhone 4, 132 for iPad etc.) but obviously that is going to increase file size by quite a bit.
So I was wondering what DPI other people use when designing universal apps? [import]uid: 7841 topic_id: 22623 reply_id: 322623[/import]
There is a big misconception on what DPI and size of an image in pixels means.
DPI means dots per inch. It only has a meaning if the image is physicaly printed. So at 300 dpi it would mean that if your picture is 1 inch by 1 inch, it has a width and height of 300 pixels.
You can have an image of 1 million DPI, but that is only 128x128 pixels in size. And have one at 1 DPI that is 1024x1024 pixels in size. Which one do you think can represent an object with best quality? Of course it will be the one that is bigger.
So, in conclusion DPI is a measure for printing, it has pretty much no meaning electronicaly.
What you should be asking is what resolution should you use for your images. And in that case you have to have in mind that a low resolution iPhone as 480x320 pixels and an iPhone with retina display has double, so 960x640. In the extreme case of iPad it will have 1024x768.
So, you should use images with a resolution proportional to the resolution of the device, considering the space you want it to ocupy on screen.
One simple example… if you wanted a background, it should have the full resolution of the device you’re targeting. If you’re talking about an image of a character for a sidescroll game, something like 128x64 for low resolution screens and 256x128 for high resolution screens should be around what you’re looking for.
Anyway, this has a lot to do with content scaling, so I can advise you to read this article: http://blog.anscamobile.com/2010/11/content-scaling-made-easy/ [import]uid: 61899 topic_id: 22623 reply_id: 90210[/import]
Yeah that makes complete sense, and if I’d taken the time and actually thought about it properly I would have realised that that was the case. Thanks for clearing it up 
[import]uid: 7841 topic_id: 22623 reply_id: 90211[/import]
And don’t forget, for the iPad 3 it will be even larger
[import]uid: 10389 topic_id: 22623 reply_id: 90341[/import]
It’s really a hard concept for some people to understand. We never measure things on screen in inches. It’s measured in pixels, but so many people creating art come from a world where they are building a 4"x 5" image at 300 dpi and they can’t fathom that is really a 1200x1500 pixel image.
Rob
It’s really a hard concept for some people to understand. We never measure things on screen in inches. It’s measured in pixels, but so many people creating art come from a world where they are building a 4"x 5" image at 300 dpi and they can’t fathom that is really a 1200x1500 pixel image.
Rob