Cloud-top heights were successfully derived from reflected solar radiation measurements within the oxygen A-band absorption. The accuracy of the estimated cloud-top heights was to within 40 meters over stratus clouds when compared with simultaneously taken lidar measurements. Estimations of the cloud optical thickness from reflected radiances at λ = 755 nm are reasonable. Between both cloud optical thickness and cloud-lop height a positive cross correlation was found to be significant at scales up to 5 km, which confirms a relationship between cloud-top height and cloud optical thickness. These experimental musts show the potential of multichannel radiance measurements for the detection of physical cloud properties. Abstract Cloud-top heights were successfully derived from reflected solar radiation measurements within the oxygen A-band absorption. The accuracy of the estimated cloud-top heights was to within 40 meters over stratus clouds when compared with simultaneously taken lidar measurements. Estimations of the cloud optical thickness from reflected radiances at λ = 755 nm are reasonable. Between both cloud optical thickness and cloud-lop height a positive cross correlation was found to be significant at scales up to 5 km, which confirms a relationship between cloud-top height and cloud optical thickness. These experimental musts show the potential of multichannel radiance measurements for the detection of physical cloud properties.