Here is a video from FreshDV‘s Film School, a series that centers on a career camera assistant explaining his job and giving advice on how to pull focus.
This particular video is one I watched when was I first learning how to pull focus.
The video is summarized as thus:
FreshDV recently sat down with Bob Sanchez, a Chicago-based career 1st A/C with 30 years of feature filmmaking experience. In part one of our video series with Bob, Kendal Miller interviews him on what exactly it takes to do the job, and the tips and tricks he’s learned over the years. Bob explains his unique method of focus pulling with a speed crank, how he approaches measuring and marking a scene, and the tools he uses on a daily basis.
The series is extremely interesting and useful. Bob Sanchez has a good way of explaining the subtleties of pulling focus as well as giving out advice that I have used from time to time.