Imami P, Filmski i TV rečnik en-sr:
head leader - vodeći blank


Larry Blake’s Handy-Dandy Film Sound Glossary:
leader - The head leader, at the beginning of each reel of a film, comprises a thread-up section that contains information about the reel’s content (such as film title, reel number, etc.). The countdown section begins with the Picture Start frame, which is considered the "start mark," followed by a numbered rundown, totaling 12 feet or 8 seconds. The last number is two seconds (three feet) before the beginning of the active picture ("first frame of picture").
( http://www.northbeachpost.com/handy_glossary.html )