Single track of metering marks on thermal printer media

A thermal dye printer media element for use in a thermal printer includes sequential color patches which form multiple color groups located along a length of the element. Metering marks are provided repetitively along the length of the element for measurement of distances along the element. The spacing between successive pairs of the metering marks may be uniform, change in a linear fashion, or change in a nonlinear fashion. The metering marks may be optically or magnetically detectable. The first and second metering mark sequences may be essentially the same. Alternatively, the first and second metering mark sub-sequences may be different. The start of a metering mark sequence may be aligned with an edge of a color patch, or may be offset from an edge of a color patch. A third sequence of metering marks may be provided for a third color patch, wherein said third metering mark sequence is different from said first sequence.