The present invention provides methods for generating interferometric information. Interferometric information from refractively scanned interferometers can contain errors due to wavelength-dependent refractive indices. The wavelength-dependent refractive indices of elements of the interferometer can produce errors when the OPD at a reference wavelength is different than the OPD at a sample wavelength. The invention can provide correction of interferometric information using relationships between the OPD at the wavelengths of interest, which correction can also be dependent on physical relationships among elements of the interferometer.