When we look at the world, the eye is constantly moving, it grabs the small pieces, and the brain combines it all into the overall picture. But if we take a photograph in which all objects are cut, then it would seem to us painted, it happens when we remove the "dark" optics or a compact camera, why? Because the depth of field depends on: 1) focal length lens, and 2) the distance to the subject; 3) The amount of solar cell, matrix it or film (behold why in compact cameras DOF always big); 4) luminosity or on much now open diapliragm; Focal distance and distance obtained binds than more focal distance the less DOF but if we want storyline in one scale on different focal lengths, we need "zoom legs" ie derogate or approached and if we shoot on telephoto lens and waste, increasing distance and increasing the depth of field. It turns out we can administer the flu only by the size of solar cell and open or close the aperture, as well as the matrix in our a camera, only the diaphragm. And now a little bit of high-aperture optics, if the clamp, close the aperture, we can always, then open it, the more value the luminosity of the lens, we did not succeed. That is, if we have a lens with aperture 2.8 aperture is close to 22 when we will need a large depth of field, or will be a lot of light, we can, but to open up to 2.8 on the lens which has a value of 4.5 – no! That is obtained by the smaller number of the more aperture, since luminosity is 1/na aperture. Remember this formula, we will not get confused as to open or close the aperture to a darkened room we had was barely visible contours on a black background, and in the solar day of overexposed persons and to reduce the depth of field, make sharp eyes only, and everything else, including debris in the street, gone in a blur.
Matrix of so-called matrix digital camera is a device with a certain amount of light-sensitive elements (Pixels). It provides the color, noise, transmission of detail and depth of field. The higher the resolution matrix of the camera, so consequently, the more he will be able to capture the finer details. The high density pixel digital camera enables the processor to build a more accurate color. The number of megapixels, thus, is responsible for a maximum resolution of photos you can make a camera without losing quality.
For amateur footage is enough for two to five megapixels. Lens When you need to pay particular attention to lens digital camera. This important characteristic, as the parameter increases (zoom), may be a digital or optical. Digital zoom is accomplished by increasing the frame after the shooting and cutting it to size, thereby losing its quality. Same optical zoom (optical zoom) is realized by changing focal length lens. In particular, it is used for larger image when physically impossible to approach the subject.
Direct impact on the cost of digital cameras has namely optical zoom, and digital is in fact a free application, since it does not actually "closer" the subject and does not change the viewing angle. Camera with optical zoom are a variety of focal range of lenses, as well as make possible the installation of replacement optics. Through this you can do as a professional narrow screen and portrait photography and large format. LCD Clear Benefits LCD is that it can immediately view the captured image, as well as shoot from awkward positions.
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