SLR camera key words and definitions

ISO is the international standards organization, International Standards Organization. The film was ISO100200and 400kinds, it is speed of different film.
ISO sensitivity is CCD ( or film) on the light sensitive degree. If you use ISO100film camera,2 seconds can be correctly exposed,camera quality will be improved the same light conditions with ISO200film need only seconds to as long as0.5 seconds, using ISO400.
In the digital era, digital camera the main menu have ISO choice,100200400or800, and the film on the same. Look at the type of different, lower to ISO50, the maximum to 25600, digital more sensitive ( the higher sensitivity ).
High ISO is fast but the image coarse particles, not fine to enlarge map. So the landscape photography to use camera minimum sensitivity can get fine pictures. High ISO in general cannot but when it is used.
The shutter is the camera exposure time control device. A mechanical shutter, electronic shutter, and the shutter and so on many kinds of electronic mechanical joint.
The aperture is adjusted in the light into the lens hole size device. Common aperture value as follows: F1, F1.4, F2, F2.8, F4, F5.6, F8, F11, F16, F22, F32, F44, F64.
The effect of the aperture
The 1hole, which directly affects the image whether the correct exposure, is the key to success;
In 2control of the depth of field, smaller apertures, the greater the depth of field. Although the focal length and the shooting distance all affect the depth of field, but the focal length and object distance change at the same time also affects the composition, if the composition determination, we can control the depth of field of the weapon is only aperture;
The 3aperture effects of picture definition, any one lens are in the medium aperture when imaging the best ( most clearly ), the maximum aperture and minimum aperture time resolution difference.
Exposure is the aperture and shutter assembly,Imaging principle by adjusting the size of the aperture and shutter speed, to ensure that the exposure effect.
Focal length
The strict definition is: standard lens is the focal distance is equal to negative ( or CCD ) the length of the diagonal of the lens.