Before you venture past the Project Settings interface to the video-editing workspace, I recommend clicking the Custom button and briefly checking out the general settings. Use the drop-down menu to access that interface. This presents one confusing aspect of Premiere and video editing in general: a collection of apparently impenetrable terms, including timebase , time display, time code, timeline, and frame rate. If you select one of Premiere's presets, deciphering these terms is a nonissue. Premiere selects a standard editing scheme with all the appropriate "Time" issues to fit your project. Despite that easy fix, a little explanation is in order. TimebaseTimebase refers to how Premiere divides its editing timeline into increments . It is not the frame rate but frequently is the same as a clip's frame rate. The timebase should match your source video standard: PAL and SECAM are 25 frames (or timeline increments) per second and NTSC is a confounding 29.97 fps (see earlier note). Film runs at 24 fps, and the default setting for Video for Windows and QuickTime is 30 increments per second. Task: Explore How Timebase Settings WorkThere's an easy way to see how timebase settings work:
If you selected NTSC, you'll see that as you move past 59:29 (59 seconds, 29 frames) the time will jump to 1:00:02 (one minute, zero seconds, and two frames). It skips two frames every minute (with the exception of every tenth minute) to compensate for the convoluted NTSC 29.97 timebase and to accommodate that standard's dropped frames. No actual frames are lost, only frame numbers . The purpose of this "dropped-frame" scheme is to ensure time-accurate program lengths (see the "Video Alphabet Soup" sidebar). If you select PAL, you'll see that each second is a constant 25 frames long, and if you chose a multimedia setting it'll be 30 fps. Much simpler. Frame RateThe only time the frame rate won't equal the timebase is when you use Video for Windows or QuickTime. You'll notice this when you use existing Video for Windows or QuickTime files as source clips. Those clips may have been made at less than 30 fps to ensure they could run smoothly on slower systems. Task: Working with the Timebase and Frame RateHere's one example of a video with a frame rate that's different from the timebase. The file sample.mov comes with the version of QuickTime bundled with your copy of Premiere. It runs at only 12 fps. Follow these steps to see the timebase and frame rate in action:
You'll see that as you move through sample.mov , the time display will skip two or three frames for each Frame Forward button click you make: 12 frames per second spread out over 30 time increments per second (the timebase) amounts to about one frame of QuickTime video per three timeline increments. It gets even weirder if you drag sample.mov to the timeline. You will need to click the Frame Forward button in the Program Monitor window two or three times before the image will change. The source side of the monitor plays the video in its original 12-frames-per-second mode. The program side plays it in the Project Setting's 30-increment-per-second mode. Time DisplayFor all intents and purposes, time display is the same as timebase. The exception again is good-old North American NTSC. If you plan to play your edited NTSC video project on a TV set, stick with what's called Drop-Frame Timecode (see the "Video Alphabet Soup" sidebar). If you'll be playing back NTSC on your PC or the Web, Non-Drop-Frame Timecode works best. If you're using PAL or SECAM, stick to their 25 fps time displays. With film, you can use Feet+Frames.
As a rule of thumb, the Project Settings interface's default presets should be more than adequate for most work. And again, if your source material is high-quality video (that is, DV or full-screen analog video), selecting projects settings to match means you'll have more output options later.
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