DSLR cameras, also called DSLR (Digital-SLR, SLR English with Single lens reflex) are a type of photographic camera single-lens reflex type (SLR), which support storage of the captured image is an electronic sensor rather than 35 mm film used in chemical photography. Among its most important features is the use of control systems for automating most of the mechanisms of both sealing devices,
Synchronization with flashes (both internal and external), and generally most camera functions, although still behave in most respects (approach shot, stabilization) as electromechanical devices like their predecessors. In most cases remain the same features (and compatibility, depending on the manufacturer) for the traditional SLR system, popularized worldwide since 1959 Nikon F.
The first difference is that the lenses are interchangeable, compatible with the objectives of SLR film (depending on manufacturer). Because these objectives were designed for 35mm film, the sensor is larger than in compact cameras. While it may be the same size of a movie (36x24 mm) (full-frame sensor, usually only in very high-end models), usually tend to be somewhat smaller (see: APS-C size sensor), in which If a 'multiplying the focal length "normally 1.5 (Nikon, Pentax, Minolta, Sony), 1.3 and 1.6 (Canon) or 2x (Four Thirds) occurs.
In compact cameras small size sensors are used, leading also shorter focal lengths and therefore a very high depth of field (almost everything in the picture into focus). The depth of field is therefore the main difference between a photograph taken with a digital compact camera or an SLR. With an SLR great control is achieved by the free choice of the ratio of the focal length and aperture, as a defocused focuses on the subject photographed.
Another advantage of an image sensor larger is the highest image quality and increased sensitivity, being able to take pictures with high ISO values with very acceptable noise level.
