Learn what's behind digital camera ratings.
Although there are no industry standards for digital camera ratings, reviewers consider certain features when evaluating camera performance. In general, tech journalists and photo experts focus on image quality and performance. Image quality is measured by how accurately the camera captures colors and shapes. Performance assesses how mechanically responsive it is to the user's input and control. Other important characteristics include the camera's size, feel and portability.
Camera testers evaluate image quality by taking pictures under different lighting conditions and examining the resulting photographs for a wide range of characteristics, including:
Some of these characteristics, like noise and sharpness, are easy enough for most amateur photographers to notice. Characteristics like aliasing and color saturation often require special equipment or computer software to evaluate. In order to give consumers the best impression of a camera's image quality without spending too much time discussing its technical features, reviewers often emphasize its most important characteristics. For example, the photo editors at CNET place an emphasis on noise, sharpness and color reproduction during their reviews.
To assess a camera's real-world image quality, reviewers also take test shots in a variety of lighting conditions. For instance, the staff members at Imaging-Resource.com take indoor and outdoor shots under sunlight, lab lighting and using the camera's flash. After assembling a portfolio of images for each camera, they can then do comparative ratings for image quality.
A digital camera's performance ratings give consumers an idea of both how easy it is to use and how quickly it can take pictures. As they do when testing image quality, reviewers look at a variety of characteristics to measure a camera's performance, including:
For most consumers, shutter lag is probably the most important of these characteristics. Shutter lag measures the time elapsed between when the user presses the shutter-release button and when the camera takes the picture. Digital cameras with relatively low shutter lag times are great for taking shots of subjects in motion, like active kids, sports players or animals. Depending on the situation, startup speed can be extremely important as well. In situations where opportunities to take photos unexpectedly arise, digital cameras with low startup speeds can quickly power on and expose their first frames.
When rating a digital camera, reviewers pay attention to more than its technical prowess; they also consider its comfort, size, visual design, weatherproofing and durability. For example, point-and-shoot cameras, which are designed for casual, everyday use, generally earn high ratings for being lightweight, slim and easy to use. Similarly, mid- to high-range cameras designed for advanced amateurs and working professionals earn high ratings for being well-balanced and reasonably lightweight. Features like the size of a camera's LCD viewing screen or image stabilization software may also be important to its overall rating, depending on its intended use.