Questions II

1.  Why should you avoid using autofocus when doing videography?
-Auto focus may acquire focus on the wrong subject within the frame.
-Auto focus may roll or shift as the subject moves within the frame.
-Auto focus may not be able to stay focused on highly reflective or complex subjects.
-Auto focus may not work at all in low-light or low-contrast situations.

2.  When is using the autofocus acceptable?
As long as the lighting is good, the subject-camera distance is relatively stable, and there isn't a lot of visual complexity or movement within the frame, autofocus can yield acceptable results.

3.  What are the 4 steps to properly set your focus manually when shooting a static subject (such as an interview)?
STEP I: Compose your shot. Make sure the camera is set to MF mode.
STEP II: Next, zoom in as far as you can on the subject's eyes.
STEP III: Adjust the focus control until the eyes are sharply in focus. Moving quickly back and forth in smaller sweeps can help you identify the sweet spot more accurately.
STEP IV: Zoom back out to compose your shot.

4.  What does the term "rack focus" mean?
Rack focus is a popular technique that shooters use to rapidly shift the viewer's attention from one subject to another along the z-axis.