Francois Roddier (IfA)

Title:	Adaptive optics (AO): all you need to know,
        but never dared to ask.

Abstract: I'll briefly describe the differences between
          "curvature" AO systems and conventional AO
          systems. I'll show how our new 36-actuator
          system performs compared to others, and give
          my own views on the future of AO in astronomy.

Claude Roddier (IfA)

Talk 2:   Adaptive optics observations of Saturn's ring
          plane crossing in August 1995: scientific
          results.

Abstract: The ring near disappearance offers a rare
          opportunity to detect faint objects orbiting
          around Saturn. Whereas the Hubble Space
          Telescope discovered 3 new objects, we
          discovered 9 additional objects that escaped
          to it. We also detected a temporary arc of
          particles possibly produced by collision of
          ice blocks near the orbit of Enceladus.
          The rings and the small satellites were
          photometrically analyzed, including an ecclipse
          of Epimetheus. A model of the rings was
          obtained showing evidence for a flared diffuse
          component and a possible warp of the ring surface.