We present candidates for optical identification of 122 X-ray sources in the central part of the HS47.5-22 field (~2.4 sq. degrees) from a mid-depth ROSAT survey (Molthagen et al. 1997). Candidates selection was based on the observations in 16 mid-band filters (FWHM = 250 A, spectral range 4000 - 8000 A) and 4 broadband (u, g, r, i SDSS) filters at the 1-m Schmidt telescope of the Byurakan Astrophysical Observatory (Armenia). Within the boxes of positional errors of X-ray objects, from one to several candidates for optical identification up to R = 24m are detected. Using the spectral energy distributions constructed from the medium band photometry, we classified the objects and determined the photometric redshifts with an accuracy of dz = 0.05 (1 + z) for AGNs and with an accuracy of dz = 0.01 (1 + z) for galaxies. New data have been obtained for faint (CR <0.2s-1) X-ray objects not identified in the Hamburg Quasar Survey and SDSS survey.