Quote Originally Posted by MattKing View Post
The difference is usually small, and generally only relevant in the exacting circumstances of motion picture work.
Usually small? Perhaps, but not always. Consider the 8-64/1.9 Angenieux 8x8B as was supplied with the Beaulieu 4008ZM. It t stops around t/3.3. Mine taught me to check all of my cine camera zooms for transmission, against the evil day when the camera's on-board meter failed.