Abstract: A device (10) for practicing playing a ball game, such as tennis, comprises an arm (29) one end portion of which carries a ball (31), such that the ball (31) is rotatable retained relative to the arm (29), and a remote end portion of which is secured to a face of a toothed pulley wheel (25) which is rotatable mounted on a swingable link means (16, 17, 18) pivotally mounted on a shaft (13). A second, larger, toothed pulley wheel (14) is rotatably mounted on the shaft (13), there being resilient means (23) for restraining such rotation. The toothed pulley wheels (14, 25) are engaged by a toothed endless belt (26).

Abstract: Several effects are described which are programmable in telecines. Variable aperture correction is described which allows appropriate correction to be applied to different types of film stock. Soft focus and distortion effects are also described. The effects can be selected for whole scenes or for frames or frame portions, to give a range of effects which can be used to improve picture quality or for artistic effect.

Abstract: The invention concerns a method of deriving a television signal representing picture information on a cinema film, and a telecine apparatus according to such method. A disadvantage of continuous motion telecine equipment of the kind using a single linear array of photo-sensitive devices is that in order to derive the standard number of active (i.e. picture information containing) lines from each film frame the line frequency of scanning the array has to be changed in accordance with the particular film format being handled and the film frame rate. The apparatus of the present specification avoids this by using a rectangular matrix of photo-sensitive devices whose interrogation is controlled by a control unit in such manner that each film frame image focussed on the matrix is scanned along a plurality of rows of the matrix with the interrogation being stepped from one row to the next during the scanning.