Image size and quality?



Image size and quality?

Have you ever downloaded an image from online and then printed it, only to get results that were less than you expected? The image looked great on your computer screen, but when you printed it, it either printed at the size of a postage stamp or it printed at a decent size but looked blurry or “pixellated”? It is because of the image resolution.

The problem was simply that most photos on the internet have very small pixel dimensions, usually around 640 pixels wide by 480 pixels high, or even smaller, and that’s because images don’t need to be very large in order to appear at a decent size and good quality on your computer or laptop, screen, or even on your mobile device. Also because smaller images download much faster on websites than larger images do.

The resolution of an image refers to the density of the pixels (or printed dots) that make up that image or graphic. The higher the resolution, the crisper and more detailed the image will be. A lower resolution will be fuzzy, and less detailed.

How can I tell?

The trouble is it’s hard to find out the resolution of an image without a photo editing programme like Photoshop – and not everyone has access to Photoshop.

Although not fool-proof, it is possible to gauge the resolution of an image just by looking at the size of the file itself. The more pixels an image contains, the bigger the file will be on your computer.

Typically images will be supplied as JPEGs, and an A4 (210mm x 297mm) image at 72 ppi will create a JPEG of approximately 500kb or half a megabyte. Remember though – to use that image in print we need the image to be 300 ppi, and at that resolution the JPEG will be around 3.5 Megabytes.

Please inquire at G10 Design and Print LTD for any queries.