This paper presents an experimental investigation and an analytical modeling of the nonlinear pixel saturation effect in digital off-axis holography. The theoretical analysis is based on a semiempirical modeling and supported by the experimental analysis. Taking into account the nonlinearity of the phenomenon, an exponential law for the high-order harmonic amplitude is proposed and validated by the experimental results. The conclusion of this analysis is that the saturation effect can be described by the use of a linear operator that involves autoconvolution of the initial object wave, even though the saturation phenomenon is nonlinear.