CLV of median contrast values measured (symbols) for plage regions in PK-027 (top panel), PK-010 (middle panel), and PKR-011 (bottom panel) images. For each bandpass, the dot-dashed line indicates the average of values measured at disk positions μ ≥ 0.9, while dotted, dashed, solid, and triple-dot-dashed lines show the respective CLV derived from calculations with PRD for models H and F by Fontenla et al. (2009), and for models F and P by Fontenla et al. (1993), respectively. For PK-010, synthesis results for model P of Fontenla et al. (1993) lie outside the plotted range.