The Mysteries of DPI...

What is DPI?

When creating printed materials, it’s likely that you will have seen these three letters written in various places, however, many people may not fully understand what they mean. Here’s out short guide in which we attempt to explain the mysteries of DPI and why it is important when it comes to creating print.

Plainly speaking, DPI stands for ‘dots per inch’ – the number of little printed dots there is in an inch of your printed document. The larger the DPI, the larger the number of dots and therefore the clearer the print, rather like the resolution on your TV, computer or smartphone screen.

Usually, the higher the DPI, the higher quality the print. However, it is not always necessary to print at the highest DPI possible. If the image you are printing is intended to be small, then a really high DPI would just be a waste of ink. As a rule of thumb, when printing letters or documents, 300 dpi will be fine.

Likewise, when it comes to branded stationery such as business cards, we would advise opting for a resolution between 300 and 400 dpi. Very high DPIs are usually only used for professional photography or large advertisements.

DPI or PPI?

In a digital file, image resolution is usually referred to as PPI (pixels per inch). This number lets the printer know the intended size of the printed image. To find out the PPI your image is set to, find the file in Windows Explorer, right-click and select ‘Properties’. Then click on the ‘Details’ tab and scroll down to see the image information.

You can also open the file in Photoshop and go to Image > Image Size. The Image Size window in Photoshop will show you the dimensions of your image as well as the resolution (PPI). You can also change the resolution here by typing a number into the resolution box and clicking ‘save’.

However, increasing the resolution of an image after it has been created can make it look blurry. This is because the existing pixels will be stretched out, and Photoshop will then do it’s best to fill in the blanks. As good as Photoshop is, this often results in a not-so-sharp image. Therefore, the DPI of the image should be set to the blank document at the beginning of the design process.

Computer Monitors and DPI

Your computer monitor also has its own DPI. When you first unbox your monitor, it will be set to a default resolution, usually around 96 or 120 DPI. This means an image set to 300 DPI will not be displayed properly on most screens with a default resolution. The default resolution is usually perfect for viewing webpages and using software, but most digital designers will opt to set their screen resolution higher so they can effectively do their work.

Understanding the DPI of your image is incredibly important when it comes to creating high-quality printed materials. Ensure you have your resolution set to the correct value for the purpose and you will avoid blur and achieve a professional looking print.

We hope this has helped you to gain a better understanding of DPI. However, if you have any further questions or queries please do not hesitate to contact your designer or one of our studio team.

Iain MacLeod-Jones