It is proposed that inhomogeneities in the deposition rate can be a powerful tool for investigating properties of growing films. The macroscopic shape of the resulting surface deformation is discussed analytically for the growth equation proposed by Kardar, Parisi, and Zhang [Phys. Rev. Lett. 56, 889 (1986)]. Computer simulations for a single-step growth model confirm the predictions based on this equation and give explicit values for its parameters. It is argued that inhomogeneous deposition also provides a new method for measuring the roughness exponent.