Operator assisted process in telecine or downconversion.
Widescreen material poses a challenge when 4:3 full frame delivery is required. Sometimes important action will take place off to the side of the frame and a simple center crop will either produce a poor composition or will entirely crop out the action.
Pan and scan is a process where a 4:3 area is extracted from the original widescreen material. The crop is not locked in the center of the screen. The operator has the ability to move the crop area left and right so no important action is excluded from the frame [Fig. 1]. This type of downconversion is the best option for 4:3 full frame deliveries but it is time consuming and can be costly.
Fig. 1. Pan and Scan to Reveal the Frame Right Action