A Lesson in Resolution
Have you ever printed an image and felt disappointed with the results? Was the image slightly blurry or pixelated? All of this is caused by the image’s resolution. Here is an explanation of what resolution is and how to avoid problems like pixelated images in the future.
Photos are made up of a series of small squares that create the image, called pixels, as shown below.
If you want to use an image in print, follow one of the below steps to see if it will work:
- You can check the image size in Photoshop by going to IMAGE > IMAGE SIZE
- If you do not have Photoshop, you can also check the image size on a Mac by opening the image in Preview and going to TOOLS > ADJUST SIZE
- If you do not have Photoshop and are working on a PC, you can check the image size by opening the image in Windows Photo Viewer.
Go to FILE > PROPERTIES > DETAILS.
This brings us to the topic of resolution.
You may download an image from the Internet or upload one that you already have on your computer, and when you check the image size it says it is 11×14 inches, like the image found below.
NOTE: These examples show the image editing in Photoshop, but you can find a similar view in the programs listed above.
In the above image the resolution is 72 pixels/inch, which looks great as digital content, but if it is printed at 11×14 it will look more like the image below.
The common term used to describe resolution is DPI.
It is important to remember that keeping images at 72 dpi for digital content is great as it stays clear on the screen, but detail is dropped in order to keep images small for digital use.
72 dpi does not work for print though.
For clear, professional quality imagery, it is important to print photographs at 300 dpi.
As you adjust the resolution, the image dimensions will reduce, as shown below.
This is the same image that was shown previously, and now that the dpi has been changed from 72 to 300 dpi, the image went from being 11″x14″ to 2.64″x3.36″. The size changes, because in order for the image to keep its clarity when it is printed, it needs to be reduced to a smaller size.
TIP: Before changing any of the sizes, be sure to uncheck the resample image checkbox. If you do not uncheck this, the image will not change sizes when you change the dpi and will remain blurry.