Canon PowerShot SD870 IS (Black)

The main purpose of RAW image format is to capture a photo with as little processing as possible. In a JPEG file, several parameters are applied to the image, such as white balance, saturation and contrast, among other things; then the file is compressed using a lossy scheme. With RAW format you are generally getting as much information as your digital camera can record with, so in essence, RAW acts very much like a digital negative. The advantage of having a large amount of data in each image is that the photographer has more to work with in post-processing, and can cull out any unwanted data manually. The disadvantage is that the files are very large, causing more room to be taken up on the camera's memory card, and also slowing down the camera's ability to capture shots because of recording time.

Another thing to be aware of with RAW format is that each digital camera manufacturer creates their own proprietary type of RAW, so not all photo processing software will work with all RAW photos.

When using handheld cameras at slow shutter speeds, or with high optical zoom, image stabilization (aka anti-shake) will help with capturing sharper images. There are two types of image stabilization, optical and electronic. Electronic, or digital, stabilization works by shifting pixels within the image frame to interpolate sharpness. Optical sharpness is attained by physical movement within either the camera body or the lens element, which compensates for handheld shaking. Of the two, optical is generally considered more favorable by most photographers.

Read more in the Digital Camera Buying Guide

The casual photographer needs a camera that is easy to carry and easy to use, so compact and ultracompact cameras make the best choice. These digital cameras are the most useful for taking snapshots anywhere, and can produce nice photos for email, web, or prints smaller than 8x10 inches.

Read more in the Digital Camera Buying Guide