Cable Reference Guide - Audio Intervisual Design, Inc.

AppendixFilmDifferent Frame Rate FormatsFilm is our final consideration. It has run at a frame rate of 24frames-per-second ever since Thomas Edison invented it. Althoughthis is a “non-standard” time code, it is sometimes used in the field.In summary, the important thing to remember is that SMPTEconveys two pieces of information: tape speed and tape position.Frame rate, is the speed at which the code will run, and frametype (30/DF/25/24), is the way in which frame positions arecounted.30. Thirty frames-per-second can be drop frame (DF) or non-dropframe. If drop frame is selected, then the actual frame count isreduced by 108 frames-per-hour.25. Twenty-five frames-per-second is the European standard.24. Twenty-four frames-per-second is the film standard.Table Appendix A-1. Frame Rate FormatsCounting Counting Method Displayed Time ApplicationRate (Hz) (Frames-per-Second) Accuracy24 24 frame Real Time Motion pictures and film25 25 frame Real Time EBU standard forEuropean television29.97 1 30 drop frame 3 Real Time NTSC standard USA &Japan29.97 1 30 non-drop frame 4 0.1 % slow USA & Japan30.00 2 30 drop frame 3 0.1 % fast Non-standard30.00 2 30 non-drop frame 4 Real Time USA & Japan129.97: Generated by all “color television” sync generators (i.e.,almost all sync generators built after 1970). This is the speedat which a “black burst” signal runs (not to be confused with“black & white”). It is a standard color signal with a “color ofblack.” Use this as your standard frame rate unless you are anexpert and have a reason not to.230.00: Usually available only in “internal crystal mode” of atime code generator, or from black & white television syncgenerators. Don’t use this non-standard speed unless you arean expert and have a good reason. This is sometimes used inconjunction with motion picture film systems.3Skips 108 frames/hour at regular intervals.4Many users prefer 30 (full frame) counting because nonumbers skip in the counting sequence, even though theelapsed time accuracy at 29.97 frame rate is slightly differentfrom real time.Micro Lynx06/22/00 A-11