Planar laser-induced fluorescence (PLIF) measurements of nitric oxide (NO) have been obtained in atmospheric pressure, laminar, partially premixed ethane-air flames. The objective was to quantify PLIF measurements in partially premixed flames across which there exists a significant range of quenching environments. In particular, we investigated two flame configurations with an overall equivalence ratio of 0.5 and fuel-tube equivalence ratios of 1.33 and 2.22, respectively. Each PLIF image was made semi-quantitative by scaling the entire image based on a single laser-saturated fluorescence (LSF) point measurement. The quantified PLIF measurements were then assessed by comparison with separate two-dimensional arrays of LSF measurements. Good agreement is found between quantified PLIF and LSF measurements in both flames at all elevations. In addition, a majority of the PLIF measurements fall within the uncertainty of the LSF measurements.