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In the application, you can select the field order of a project by choosing Properties from the File menu and clicking the Video tab. The pre-configured templates should work for almost everyone (e.g., if you are editing and outputting DV video in the US, select the NTSC DV template). If you have problems, you can manually select a different field order on the Video tab. You can also override the project settings and set the field order when you render a video file. From the File menu, choose Render As. Then, click the Custom button and choose an option from the Field order drop-down list on the Video tab. You can also set field order at the level of the media file or event. Right-click a media file in the Project Media window or an event on the timeline and choose Properties. The Field order drop-down list appears on the Media tab.

Interlacing problems only manifest themselves on television monitors. Video that is going to be played back on a computer does not need to be interlaced, and you can select None (progressive scan) for the field order. Rendered video must be displayed on a television monitor to identify any problems. The only way to see interlacing problems is to record (print) a rendered video file out to tape and play back the tape on a television. Problems are most apparent in video that has a lot of motion or that has been modified in some way; for example, a slow-motion effect. (Some codecs force the correct field order during a render, making it difficult or impossible to create video with the wrong field order.)

Solving interlacing problems in Vegas software

If your hardware’s documentation does not contain any information about the proper field order, you must determine this information for yourself. It is not a difficult process, and involves rendering one video file with an upper first field order and another with a lower first field order. Source material that dramatically and clearly demonstrates the improperly interlaced video is important: use a media file with a lot of motion in it and then slow the event down with a velocity envelope or by time-stretching the event.

Timecode

Timecode is a method of labelling frames with a unique and searchable identifier. It is primarily important for synchronizing video (in frames per second) with time in the real world and, in the case of Vegas software, with other media in a project.

Changing the timecode used to measure a video file does not alter the contents of the file. For example, no frames are ever dropped or removed when using SMPTE 29.97 drop frame timecode. Instead, specific frame numbers are periodically dropped to compensate for differences between timecode and time in the real world. Confusion between using drop versus non-drop timecode can cause synchronization problems between video and audio. For very short periods of time, the error would be unnoticeable. After about a half an hour, you might notice that mouths and words do not quite match in shots of people speaking. Longer stretches of time show larger discrepancies in synchronization.

Changing the timecode displayed on an event is not equivalent to converting a video to another format. You cannot convert NTSC video at 29.97 fps to PAL video at 25 fps by simply changing the timecode. To convert NTSC video to PAL video in Vegas software, you need to re-render the video in the new format. In this situation, the conversion process necessarily results in some frames of video actually being removed from the original sequence.

SMPTE timecode types

The following are descriptions of each of the Society of Motion Picture and Television Engineers (SMPTE) timecode types.

SMPTE 25 EBU (25 fps, Video)

SMPTE 25 EBU timecode runs at 25 fps, and matches the frame rate used by European Broadcasting Union (EBU) television systems.

Use SMPTE 25 EBU format for PAL DV/D1 projects.

APPENDIX A

TROUBLESHOOTING