DxOMark rating
The result shown by the lens in the DxOMark rating.
DxOMark is one of the most popular and authoritative resources for expert testing of photography devices. According to the test results, the lens receives a certain number of points; The more points, the higher the final score.
Viewing angles
This parameter determines the size of the area of the scene being shot that falls into the frame. The wider the viewing angles, the larger the area the lens can capture in one shot. They are directly related to the focal length of the lens (see "Focal length"), and also depend on the size of the specific matrix with which the optics are used: for the same lens, the smaller the matrix, the smaller the viewing angles, and vice versa. On our website, in the characteristics of optics, viewing angles are usually indicated when used with the matrix for which the lens was originally designed (for more details, see "Matrix Size").
Design (elements/groups)
The number of elements (in fact, the number of lenses) included in the design of the lens, as well as the number of groups in which these elements are combined. Usually, the more elements provided in the design, the better the lens handles with distortions (aberrations) when light passes through it. On the other hand, numerous lenses increases the dimensions and weight of the optics, reduces light transmission (for more details, see "Aperture") and also puts forward increased requirements for the quality of processing, which affects the cost of the lens.
Number of diaphragm blades
The number of blades provided in the design of the diaphragm (for details, see "Minimum aperture"). In fact, this parameter is important when shooting scenes with pronounced bokeh (blurred background) and a small depth of field: the more petals the aperture has, the smoother the glare from out-of-focus objects will turn out, while with a small number of petals they can look like polygons. The number of aperture blades has almost no effect on other shooting parameters. Modern lenses have an average of 7-9 petals; the smoothing provided by them in most cases is considered quite sufficient.
Dustproof & waterproof
Lenses with protection against ingress of dust and moisture. "Protected" optics are useful primarily for those who have to shoot a lot outdoors: they are much more resistant to bad weather than ordinary ones, many of these lenses work quietly in the rain, sea spray, etc. However, the specific degree of protection for different models can significantly differ, this point should be specified separately in the official documentation of the manufacturer. Also note that if you intend to constantly shoot in difficult external conditions, not only the lens, but also the camera itself must have dust and water protection.
