- Various pushbroom imaging spectroscopy systems experience low-frequency array effects that are often referred to as spectral curvature effect or smile/ frown interferences. The smile effect may render spectral absorption positions, leading to inadequate atmospheric correction and a noisy reflectance product; as a result, the thematic spectral based products may be erroneous e.g., thematic misclassification of the data. A method for the correction of spectral curvature effects (smile) in Hyperion (EO-1) images, termed "Trend Line Smile Correction" (TLSC), is presented. TLSC operates a precise modification to the MNF-1 band, based on the evaluation of the smile effect according to absorption features of well-mixed gases. The methodology was tested on four different Hyperion scenes and consistently outperformed other tested methods by up to 9 times.