  In this paper, we introduce isophote curves on surfaces in Galilean 3-space.
Apart from the general concept of isophotes, we split our studies into two
cases to get the axis d of isophote curves lying on a surface such that d is an
isotropic or a non isotropic vector. We also give the method to compute
isophote curves of surfaces of revolution. Subsequently, we show the
relationship between isophote curves and slant(general) helices on surfaces of
revolution obtained by revolving a curve by Euclidean rotations. Finally, we
give an example to compute isophote curves on isotropic surfaces of revolution.
