A pixel is a term for a single point in a graphic image. The term was created from shortening “picture element” and using the common abbreviation “pix” for “picture”.
The quality of a photo can be expressed in pixels per inch (ppi) or dots per inch (dpi). They are equivalent, meaning, a photo with 72 ppi would have 72 dpi. Images shown on computer screens and web sites are acceptable at 72 ppi. When wanting to print your images, an acceptable print quality is achieved when a photo has 300 ppi or more. When printing an image that has fewer than 300 ppi, the image becomes “pixillated”. This means that individual pixels are visible resulting in blocky edges and general blurring. An image that is pixillated can be reduced (made smaller) which will make the pixels closer together and improve the image quality.
Cameras are distinguished by their resolution or how many pixels the image sensor contains. One mega pixel equals 1 million pixels. For example a 5-megapixel camera can make excellent 8x10s and acceptable 11x14s. If you want to be able to print larger photos you will need a camera that saves more pixels for an image.
Pixels and scanning: When we scan your photos, we typically set them to scan at 300 ppi. However, we can scan images as high as 1200 ppi. This allows us to print enlargements and maintain excellent print quality.