Some models from Nikon Olympus and Pentax can take pictures from a distance of 2 cm minimum shooting distance of the vast number of models in the macro mode is 5 to 20 cm It can be noted that for cameras amateur class minimum focusing distance is mostly within 10-20 cm, for vehicles of the middle class – 5-10 cm, while the semi-cells, this value is often less than 5 cm Technically macro with a digital camera quite simple: pressing a button (the icon resembling a tulip silhouette image) takes the camera in macro mode. This allows you to take pictures at close range without any adjustment optical system, camera and without using additional devices. To zoom in, shooting in some models of cameras still required the use of additional optical heads, screw-on rim of the lens. The size of the CCD camera of the middle class with an integrated lens is usually 1 / 1, 8 or 2 / 3 inches. Realistically, this means that a 'full-length' can capture small insects (Bees, beetles, bumblebees), as well as smaller items such as jewelry, coins, badges, etc., in smaller sizes to photograph the flowers, the details of everyday items or parts of the face.
Maximum scale images for digital cameras is not more than 1:2,5-1:3. For the form factor the CCD 1 / 1, 8 inches (common size for the cameras of the middle class) the size of the matrix on the long side is equal to about 7,2 mm. Consequently, when print size 15×20 magnification factor is approximately equal to about 28 times, and the image scale is about 11:1-9:1. In other words, the increase is achievable subject to 10 times on the print at a moderate its format. Should mention about one particular macro digital camera – a great depth of field. Close-up images of traditional analog camera depth of field is usually small. This is due to large size focal length lens. And what is more (which is preferably close-up photography), the less depth of field, more precisely, the depth of field.
It is known that there is an inverse quadratic dependence of depth of field on the focal length and a linear dependence on the distance to the subject. Thus, at equal magnification large depth of field is provided short-focus lenses. Focal length lens digital camera several times smaller than the film. Therefore, the depth of field at equal magnification greater than a few times. (For convenience, the real value of the focal length of lens digital cameras are often reduced to the equivalent focal length lens uzkoplenochnoy camera). (C) Boris Semenov
