Dirty or deteriorating video tape can leave foreign material on the tape path around the head drum. The building up foreign materials will distort the tape, causing poor head-to-tape contact and in turn causing visible errors in the video signal. The example included here comes from a U-matic tape, and appears as a grainy and discolored line across the frame. This error may look different across different tape formats.
Can it be fixed?
Cleaning the tape path of your VTR and cleaning the media may help reduce this artifact.
This example shows a dirty head drum error on a U-matic tape. The error is visible across the antire frame, and appears right under David Hockney’s chin.