What Is Field Order?

All video displays, whether analog or digital, work by breaking a single frame of video into individual lines of horizontal resolution running across the screen. Standard definition NTSC and PAL are both interlaced video formats, as opposed to high definition video, or video displayed on a computer screen, which are progressive-scanned video formats. With progressive scanning, these lines are drawn one at a time, from the top of the screen to the bottom.

Interlaced video, including NTSC and PAL, works differently. When you record footage with your camcorder, each video frame is broken down into two fields, each containing half of the total lines of resolution in the frame. The first field is recorded, then the second, and both are laid down to tape, one after the other, so that both fields constitute one frame. When you play the tape back, a television monitor displays each recorded frame in two passes, first drawing field 1, then drawing field 2.

Field order refers to the order in which video fields are recorded from your video equipment to your hard disk. If you remember that video fields come one after another in time, as if playing 60 “frames” per second, it becomes a little easier to understand.

There are two options for field order:

Generally, Upper is used by 640 x 480 systems, while Lower is most common in professional 720 x 486 and DV 720 x 480 systems.

It’s important to render digital video with the field order used by your hardware. Because motion continues from one field to the next, it’s crucial that each field plays in the correct order. Because different capture cards handle interlacing differently, choosing the correct field order ensures proper playback.