Fig. 21.

Flatfield correction maps for filters R0, R3, and R6 at zoom levels of 34 mm (left, ${\mathit{zoom}}_{mc}=2448$), 63 mm (middle, ${\mathit{zoom}}_{mc}=5196$), and 100 mm (bottom, ${\mathit{zoom}}_{mc}=8652$). Note that the vignetting on the left-hand-side of the array, likely caused by the edge of the filter encroaching into the field of view, decreases for longer focal lengths