2-3 pull down (Film-Video Transfer)   

 
One of several methods used to transfer film to video. 

In North America this means filmís  24 frames per second to videoís  29.97 frames/second.  If one considers that a video frame is made up of two interlaced fields and that having a video frame with fields from two different film frames generally isnít too disturbing to the viewer then one can imagine how this might work. 

 
Essentially it means frame 1 goes to 2 fields, frame 2 to 3 fields and frame 4 to 2 fields (etc.) This 2-3 ratio (24-60) works well except for the occaisional instance when a single video frame contains two fields which differ a great deal (such as at a cut, etc.).  Adjusting for the slight difference in speed/image is done through time code (see drop frame) and through changing the speed of the audio track (see pull up and pull down).