As a graphic designer agency one of the most frequent requests we get during conversations with clients is to explain image pixelation to them. It’s a topic that eludes most people until they find themselves facing a low-resolution jpg retrieved from the internet and – frustrated - realise that they can’t simply enlarge a low-res image. But why?
It really depends on whether the file is a raster or a vector image - but, if you’ve retrieved it from the internet, chances are it’s a low-res raster. Raster images are made up of many little dots (pixels); they sit next to each other in rows, side by side. When you want to make the image smaller, you essentially just remove every second, third or fourth row and column in the formation, and squish the remaining pixels together until they’re touching again. You’re removing information - not a problem. The retains a crisp, sharp image, as long as you’re looking at it at the intended size.
If you want to enlarge a raster image, however, that’s a different story. The pixels themselves don’t change size, they just spread out to cover a large area. As you can imagine, this creates gaps between the pixels where there is no information - your computer tries to guess what colour to fill these gaps with, based on the information surrounding the gaps. It can be pretty accurate, up to about 10% larger than the original file. After this, you’ll start to see pixelation because the computer cannot make an accurate guess on how to fill this space anymore.
Moral of the story: you can always shrink an image, but you can’t always enlarge it.
Our top tip: if, for some reason, you’re working only with raster files always, always, always make a copy of the largest file you can. That way, if you accidentally save the file at a smaller size, you have a back up.
Ideally, of course, when dealing with design files your designer should always provide you with a live, editable vector graphic, from which you can export smaller and more widely used files.
If you find yourself with a sub-par raster graphic, feel free to reach out at inksplotdesigns@gmail.com - we can’t improve the file, but we can re-create properly it for you.