Angle ∠BAC might refer to any of four angles: the clockwise angle from B to C, the anticlockwise angle from B to C, the clockwise angle from C to B, or the anticlockwise angle from C to B, where the direction in which the angle is measured determines its sign (see Positive and negative angles). However, in many geometrical situations it is obvious from context that the positive angle less than or equal to 180 degrees is meant, and no ambiguity arises. Otherwise, a convention may be adopted so that ∠BAC always refers to the anticlockwise (positive) angle from B to
Screen angle depend on how many colors are used and the preference of the press operator, typical CMYK process printing uses any of the following screen angles: Screen angle In offset printing, the screen angle is the angle at which the halftones of a separated color is made output to a lithographic film, hence, printed on final product media. In offset printing, colors are output on separate lithographic plates. Failing to use the correct set of angles to output every color may lead to a sort of optical noise called a moiré pattern which may appear as bands or waves in the