The paper presents a study of the structure of the photoconductivity spectra of various 4H-SiC samples near the absorption edge. By means of comparison of the spectra of low doped (mid 10(14) cm(-3)), very low doped (in 10(13) cm(-3) range), and semi-insulating moderately doped samples, features in the photocurrent due to contribution from creation of free carriers (i.e., excitons in the continuum) can be recognised. This is used for determination of the free exciton binding energy, 20.5 +/- 1 meV, in agreement with a previous study. The second lowest conduction band and the spin-orbit split off valence band are also detected.