A simple technique has been used to investigate the linearity of response of Kodak 10101 EUV film at low exposure levels. Radiation at lambda approximately 18.2 nm from a laser produced plasma and at lambda approximately 17 nm from a Garton flash tube were used in separate experiments to study the response for ns and mu s exposure times. This film responds linearly up to film densities of 0.45 D above fog. The technique is generally applicable to films recording spectra from the X-ray to VUV regions.