Everything you need to know about Image Resolution, DPI Printing, and Dots Per Inch System

If you are working in the creative field or use printing services on a regular basis, you’ve probably come across the term 300 DPI a couple of times. In this article, you will learn what the DPI meaning is and why it is important for printing. Read on to find everything you need to know about Image Resolution.

What is DPI?

Let’s start with the abbreviation of DPI. DPI stands for Dot Per Inch and describes a method of spatial printing, where individual dots of color are placed in the line within the span of 1 inch or 2,54 centimeters. Higher DPI means higher Image Resolution and vice versa. The low DPI (and hence bad Image Resolution) fluctuates between 60 and 96 DPI, while the highest DPI available at the moment is 2,400.

Here’s the picture that might help you better understand how Dot Per Inch system works on practice:

Image representing DPI printing system

Source

The higher dot density is the better quality of your image will be.

When Do You Need to Have 300 DPI Images

If you are working with files of small size, it is not that important to have high DPI. However, planning to print products of larger formats (like roll-up posters and banners), you need to ensure that your artwork file is set to 300 DPI. By doing so, you will get high-quality prints that look bright and detailed. If you ignore this rule, you will get the result, which looks something like the photograph on the left.

Comparison of Images with Low and High DPI

How Does DPI Resolution Depend on the Image Type?

When printing Raster Graphic Images, which are also known as Bitmap Graphics (images that are arranged in a grid of pixels), it is important to pay attention to DPI. When zooming in, such images will turn into a bunch of pixels and won’t look like a proper artwork.

It’s different with Vector Images (that are usually created in Adobe Illustrators) as they are based on mathematical formulas and automatically adjust to different sizes. If you have vector images, you shouldn’t worry about DPI that is too low.

How to Find Out what DPI Your Image Is

If you are a Windows user, the easiest way to find out your image DPI is to follow these steps:

  • Right click on the image you want to check
  • Go to “Properties”
  • Click on “Details”
  • Scroll down to the “Image” Section
  • “Horizontal Resolution” and “Vertical Resolution” is the information you are looking for!

If for some reason you don’t see your DPI, you can use “Paint”, a Software available on all computers powered by Windows. Simply upload the file to Paint, click the “File” tab, and choose properties. The third line will show you your image DPI.

For Mac users, here’s how you can find DPI:

  • Open the image in “Preview”
  • Click the “Tools” tab at the top and then go to “Adjust Size”
  • Voila! You can also change your DPI in there by unchecking the “Resample Image” box.

How to Change Image Resolution

While it is possible to reduce the Image Resolution, there’s no way to increase it (except for making a new picture from scratch).

You can easily change your DPI in Photo and Image Editors such as Adobe Photoshop and Illustrator or use an online service such as Convert Town or DPI Converter.

The Last Piece of Advice

Before printing your artwork, make sure that you changed your color mode from RGB to CMYK. You can read more about the difference between the two in this article. Also, check our material about artwork preparation for larger formats here.

If you have other questions about preparing your artwork for printing, go to Resources Page or simply call our Customer Support Team at (02) 8488 3160 and we will happily answer all of your questions and help you print banners and roll-up posters of larger formats.