Prime Focus Spectrograph (PFS) for the Subaru telescope: 2D modeling of the point spread function

Prime Focus Spectrograph is a state-of-the-art multifiber spectrograph being installed on the Subaru telescope. High-quality sky subtraction is of crucial importance for its successful operation. Here we describe the status of the development of modeling algorithms for point spread function determination and subtraction of skylines. Defocused data taken with dedicated lamps allows us to determine the illumination properties of individual fibers, and to determine wavefront aberrations that are present in the instrument. Based on those inputs, we are able to model the point spread function in 2D and achieve sub 1% subtraction quality for significant parts of the wavelength range covered by the available data.