How to increase the size of your image without losing the clarity

Printing high-quality artwork is critical to ensuring a superb result.

If you've got bitmap artwork, a photo, for example, that is less than 300DPI it may not print correctly. This article will tell you how to increase the size without sacrificing quality.

Note: this method works to approximately double the size of your design without losing quality. If you need much more than that, the best option is to source new artwork.

What happens when you usually scale up a bitmap

Bitmaps are a collection of thousands of tiny coloured squares, known as pixels. You need about 300 pixels per inch (DPI) to make it look high-resolution to the human eye.

If you scale up your bitmap artwork, you are merely increasing the size of these pixels. If you do this too much and the DPI falls below 300 per inch, this may cause problems. 

A good rule is "You get out what you put in". The higher quality artwork you can provide the higher quality your sticker or label will print.

For example, suppose you send or receive an image on Whatsapp. In that case, it will reduce the quality by compressing the photo to make it smaller; this will not be suitable for printing on a large scale.

How you scale without losing quality

The technique for scaling artwork by 2x without losing much quality is to add pixels. You can use a tool that splits each pixel into four and uses intelligent algorithms to judge the exact colour of the new pixels. Very clever.

How do you do this?

There are a few options explained below:

• Use resizing.app. Upload your image, set parameters such as height, width and click start. Seconds later, your file is ready for download. And it's free!
• Use Adobe Photoshop. Not recommended for beginners. It has a tool called 'Perfect Resize'. To use it open the image you want to resize in Photoshop then click File, Automate, and select Perfect Resize. A new window will open where you can either choose from a selection of preset resizing templates or input your dimensions. Once chosen click File, Apply.
• Use GIMP. GIMP is an open-source (& therefore free) tool for manipulating images. To resize a photo, open it in GIMP, go to image > scale & enter your desired dimensions. Finally, under the quality section, choose 'Sinc as Interpolation' and then click scale.