Resolution in digital photography relates to how detailed and high quality your picture is. The detail is determined by the number of pixels in your photo.
Every digital image is composed of little pixels. Each pixel in a photo is smaller than a computer screen pixel. Computers usually display about 72 pixels per inch, whereas on paper you may print off a shot with 300 pixels per inch. The more pixels there are per a photo, the higher the quality of the image. For this reason, resolution is often measured in megapixels (millions of pixels per image). The resolution is determined by the quality of the camera's technology.
A camera that captures images that are 1920 pixels high and 1080 pixels wide is said to have 1920x1080 resolution, or around 2 million megapixels. Incidentally video quality is also measured in this pixel-related resolution, and 1080 pixel width (1080p) is the common image width for high quality blu-rays and some HD discs. Most DVDs are 720x480 pixels (720p) and normal analog TV broadcast is around 500x480 (480p). Youtube videos allow you to set your resolution from 240p to 480p.
Still cameras generally have higher resolution than 2 megapixels with the best ones having up to 8 or more megapixels.
The higher the resolution, the higher the quality of your shots, so you can zoom in on a shot and still retain detail, and you can blow a photo up to a large size and it'll still look good. So really, the higher the resolution, the better.
Can you change your camera's resolution for individual shots?
Yes. On my camera there are settings for:
- Large (L) which is high resolution at 3264x2448 pixels (ie 8 megapixels)
- Large to medium (L/M); Medium (M); and Medium-to-small (M/S) settings which vary in resolution
- Small (S) which is the lowest resolution at 640x480 pixels (ie 3 megapixels)
