Not sure if Alex posted this already but there's an overview paper in press at Planetary and Space Science of the HSRC instrument.
The high resolution stereo camera (HRSC) experiment on Mars express: Instrument aspects and experiment conduct from interplanetary cruise through the nominal mission • ARTICLE
In Press, Accepted Manuscript, Available online 30 December 2006
R. Jaumann, G. Neukum, T. Behnke, T.C. Duxbury, J. Flohrer, S.V. Gasselt, B. Giese, K. Gwinner, E. Hauber, H. Hoffmann et al.
link to PDF (for those who have access)