You can set an In point in the Viewer, Canvas, or Timeline window by clicking the appropriate button under the Viewer (if you are setting a source clip's starting point) or the Canvas and Timeline (if you are setting where it starts in the sequence). Out points are set the same way, with the respective Mark Out buttons in the Viewer or Canvas. The keyboard shortcuts are the best way to set In and Out points in the Viewer, Canvas, or Timeline. Press I for in and O for out. The I and O keys are right above the J, K, and L keys, used to shuttle the video in all three windows . You should get into the habit of using these five keys to move, mark, and creep through the footage (L or J +K) to mark your In and Out points most of the time. If you have time-code numbers , such as those given for the Workshops in this book, you can either type them in or get used to using the J, K, and L keys to shuttle to them. Also don't forget that pressing the J or L key more than once speeds up the shuttling process (L for play and J for reverse). By pressing the left or right arrow key, you can go through your footage backward or forward a frame at a time to locate just the right frame at which to set an In or Out point.
You don't have to pause to set an In or Out point. You can set it as you play the video or audio in either the Viewer or the Canvas. You can continually press I to update the Mark In point or keep pressing the O key to keep updating the Mark Out point as you watch the video. Each time you press I or O while you watch the video, the new point gets set. This is great for getting a quick update or making a change as you watch the video play. A constant updating of the In or Out points really helps move your editing along. This works well when you don't know exactly where a pan might end or a zoom or dolly might end or start. It also helps you set the pacing and timing of edits (finding the rhythm of the beats, as mentioned in the sidebar). In the case of an interview, it's great to update an Out point when the next sentence is finished. As soon as you start setting points this way, you'll see the advantages. Try it. You'll like it.
You can't set more than one In point or Out point in the Viewer unless the source material contains audio and video. If the clip contains more than one track of media, you can perform split edits. With split edits, multiple-track source clips (such as sound sync audio and video clips) are marked so that the audio and video are edited into your sequence at different times. For example, you show the video and then add the audio a bit later, or you hear the audio before the video that syncs with it.
However, there's a way to perform split edits more intuitively. First, you cut the audio track the way you want to hear it using audio/video cuts along the way (it helps to set your timing and the scene's rhythm too). After you have performed this rough cut, unlink the synchronized audio from the video clip it's associated with by pressing the unlink button in the upper-right corner of the Timeline window or by pressing Shift+L. Then perform roll edits on the video track. Roll to the left or right. The split edit then gets performed in this manner. An even faster way is to use the Roll edit tool while holding down the Option key. This temporarily unlinks the video clips from their linked audio.