Noise on the ALFOSC CCD appearing as bands continued to be present. Initially it was assumed the noise was pick-up of some kind, though after numerous tests with the cables no improvement could be made. At some moment the noise started to become worse to such an extent it could affect the science. By exchanging some of the ALFOSC controller boards with similar ones from the SOFIN CCD controller, eventually it was found that the clocking board in the ALFOSC controller was the source of the noise and a spare was installed which has solved this problem.

Thomas Augusteijn 2009-05-14