Photography Terms

English abbreviation for Multi Coated. Indicates that antireflective, multi-layer coatings prevent or reduce reflections of light from the surface.

UMC

Ultra Multi Coated, the abbreviation indicates that a lens or filter has been covered with multi-layered, anti-reflective coating which minimizes reflections and increases image contrast. UMC coatings had replaced MC layers previously used in Samyang Oprics products.

English abbreviation for Internal Focusing. Indicates that focusing lens in the photographic lens is not an external lens. Owing to this solution, front and last lens elements do not shift or rotate, which is significant if filters or lens screens are used.

PRESET LENS b

a lens equipped with a ring adjusting the diaphragm.

abbreviation which indicates that a photographic lens is equipped with a lens or a few lenses with low dispersion. If such lenses are used, elements of the visible spectrum are dispersed at a small angle. This type of lenses allows to minimize the chromatic aberration.

CHROMATIC ABERRATION

a feature of a lens or an optical system resulting from different focusing distances for the given colours of the light spectrum. As a result, „fringes” of colour occur along the contrasting boundaries of the area visible through a lens. ED lenses are used to minimize the chromatic aberration.

ASPHERICAL

a lens with an aspherical lens, in which at least one of the surfaces is not a portion of a sphere. This shape allows to eliminate the spherical aberration. In this defect non-axial rays of light focus in different points and blur the image. Aspherical lenses include Samyang 85mm f/1.4 IF MC or Samyang 8mm f/3.5 fish-eye IF MC.

MIRROR LENS

telephoto lenses which are equipped both in lenses and parabolic mirrors. Thanks to this construction, length of the housing gets smaller while its axis bigger. Another distinctive feature of the mirror lens, is that there is no possibility to change the diaphragm. Construction scheme of a mirror lens is presented below.

FISH-EYE

a lens providing extremely wide angle of view. It produces specific image distortion, the so called barrel distortion, which is not supposed to be corrected for aesthetic reasons . There are two distinctive types of fish-eye lenses:
a) circular – image is projected as a circle within the frame
b) full-frame – image circle covers the entire film frame
Sample photo taken with a fish-eye lens.

DISTORTION

image deformity or aberration resulting from optical construction of a lens or caused by large distance of a subject from the optical axis. Photographers may usually experience barrel and pincushion distortions.

Sample of distortion

BOKEH

a Japanese term which refers to the aesthetic quality of the blur in out-of-focus areas of an image. Bokeh is a relatively subjective term and depends on individual preferences.

DEPTH OF FOCUS

is a measure of distances for which objects on the image are appropriately sharp. Depends on the focus, distance of the imaged subject and the size of a sensor (or analogous carrier), and is connected with the lens’s focal length. Basically, the smaller focal length, the larger depth of focus.

VIGNETTING

flaw on the image, partial reduction of brightness or saturation on the periphery of the frame. Vignetting effect reduces proportionally with the increase of the aperture size.