You can even toggle between drop frame and non-drop frame in most non-linear timelines. Your camera person can shoot in 24 fps and you can capture in 30 fps drop frame or non drop frame. Editing systems can now accept a myriad of formats and frame rates. One format is not better than the other when it comes to your editing system. 60 minutes of non-drop frame format will be 108 frames lower, making it 00:59:56:12 at the end of a real time hour 01:00. A program using non-drop timecode is approximately four seconds shorter per every hour. It is counting 3000 frames per 100 seconds when it's really 2997 frames per 100 seconds. This makes non-drop lengths shorter than the real time. This means that if you have a 60-minute film and 0 frames in non-drop frame timeline, it is not the actual running time of the film. Non-drop timecode counts every single video frame and doesn't re-label any frame to account for the 29.97 fps. Drop frame is a standard for broadcast networks using NTSC due to this correlation with real time. If you are cutting a scene using drop frame time code, the duration of 60 minutes is exactly 60 minutes and 0 frames. 2,997 full frames are presented every 100 seconds. The way they are being counted has been changed. This means ten minutes in drop frame 00:10:00:00 is the same as 00:10 minutes in real time. There are never any frame numbers dropped when the minute is divisible by 10. The distribution of those 18 frames equals about 2 frames (:00 and: 01) a minute, but no frame numbers are dropped in the 10th minute because the process has started over. These frame numbers are dropped over time instead of all at once. Moving the decimal place over from 1.8 frames per minute produces 18 full frames for every 10 minutes. 03 second of 29.97 finally adds up to a video frame, it drops a frame number. Drop frame timecode counts each video frame. Since creating a fraction of a frame is impractical, a method of counting and adjusting full frames is necessary. The 29.97-second frame rate does not divide into one second as easily as 30 fps does. It's this slowdown of frames that causes the disparity between real time and the measurement of video time. Color video required that the frame rate be slowed to 29.97 fps, due to the physical limitations of the black and white circuits in older television sets, and issues involving sound waves. Originally, black and white video ran at a true 30 fps (Frames per Second). Understanding frame rate helps us understand why these two methods exist.įrame rate is the measurement of individual images, known as frames created by an imaging device. Since this does not affect the picture, choosing between drop or non-drop frame can be determined by the specifications of the editing system, distribution media, or video editor’s preference. If two projects were created with identical cuts, both timelines in the software would be identical. No frames or images are lost in drop frame it is simply a way of labeling every frame. You can find out more about timecode in a previous article on the B&H web site, Understanding TIME CODE- part I By Robert Morton & Jack Fettman.ĭrop frame and non-drop frame timecode do not alter the visual image in any way. Every frame is given a unique timecode number, making it easily found by a non-linear or linear device that utilizes and reads timecode. It measures time in Hours:Minutes:Seconds:Frames and creates a distinct identifier for each frame, based on the HH:MM:SS:FF format. Timecode is used to provide search ability on your tapes, disks, and other media. Drop frame and non-drop frame were created before High Definition (HD), but the same rules still apply. B&H Photo Video understands the multitude of video formats that can be used in a single project this article will hopefully clear up some of the confusion caused by the concepts of frame rate, broadcast standards, and accuracy involving timecodes. Understanding the basics of drop frame (DF) and non-drop frame (NDF) can help keep your work flow running smoothly.
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