What resolution do my images need to be?

We are often asked ‘what resolution do my images need to be?’ The answer to this question varies on the intended purpose of the image. This helpful guide should point you in the right direction if you're unsure.

In the world of small format printing, the rule of thumb is usually about 300dpi. Higher than that and the file size increases without truly increasing quality, lower than that and you may see jagged edges and areas of contrast. 

But in the world of large format printing, this question is more involved. 

Images on huge banners, wall graphics or billboards can be 12 by 3 metres or larger. At 300dpi an image at this size would be an almost unworkable 10GB file size. For this reason, when artwork is created for print that exceeds 2 metres we advise working at 10% with your images at 300dpi; this allows us to process the imagery, then magnify and print the target resolutions at final size.

The guidelines for determining image resolution for large format depend on 3 factors: viewing distance, the viewing conditions, and the type of image. 

Viewing Distance 

As we view things from further away, our ability to see detail diminishes but also the larger an image is, the further you need to stand away in order to be able to view it in its entirety. Below is a table of example products and viewing distances with the maximum resolution under ideal conditions: 

 
So this gives us a guideline to estimate the amount of resolution required for a given output size. 

Viewing Conditions 

The next consideration is how the image is viewed. Is there ample illumination? Will it be moving? Will the viewer be moving? Is it possible that the viewer may be much closer than the estimated viewing distance?

For example, consider an interior wall graphic and a billboard may have the exact same dimensions, but very different viewing conditions. Interior wall graphics most likely will be well lit and viewed quite close up. So in that instance, higher resolutions would be necessary. For the billboard, it would not be as critical, since it would be viewed when you are moving, under variable lighting conditions. 

The Image 

The last thing to consider is the image itself. A low contrast or soft focus image can be quite acceptable at lower resolutions, whereas an image with high contrast edges or fine lines will show an obvious lack of resolution. Does the image have a high degree of detail that needs to show clearly, such as hair or fabric? Finer details may require higher resolutions to render properly. 

When in doubt: just ask for our advice. If you still have concerns about the output quality, ask for a 100% sample of the image to be printed for approval. 

Still need help?

If you still need help, please fill out our Contact Us form and a member of our team will be in touch.