Image Resolution

Resolution, also known as DPI (dots per inch) or PPI (pixels per inch), can be described as the number of dots that fit horizontally and vertically into a one-inch space. Generally, the more dots per inch, the more detail captured, and the sharper the resulting image. The problem with measuring resolution in this way is you have to also know the physical dimensions of the image. That is why we prefer to measure resolution in pixel dimensions.

You can always reduce resolution, but you can’t increase it without suffering a loss in quality.

You cannot change the resolution from very small to very large. This is going to be problematic. The resulting image will become pixilated and blurry. The best solution here is to start with the largest image you can. For best print quality, photos should be 300 PPI. Photos printing with a lower PPI can print grainy and blurry. Photos used on websites have different requirements than photos for print. Most photos taken from websites are 72 PPI (by print standards, this is low quality and unusable in most cases).

Finding an Image Size in Mac OS X

First, locate the image that you are trying to find the pixel dimensions of. If you have a two-button mouse, simply right-click on the image; a menu box should appear. If you do not have a two-button mouse, you can control-click on the image. Once the menu has appeared, select “Get Info.” A new box will appear. Under the “More Info” section, you will see a line that says “Dimensions.” These are your pixel dimensions. Any image below 600 pixels wide is not recommended.

Finding an Image Size in Windows

First, locate the image that you are trying to find the pixel dimensions of. Right-click on the image so that a menu block appears. Scroll down to “Open with”, and then select “Paint.” Once the image is opened in Paint, click on the “File” menu bar, and select “Properties.” The window below will open and show you the image’s pixel dimensions. Any image below 600 pixels wide is not recommended.