Images taken during the May 1999 prime-focus imaging run were found to be slightly elliptical. The images taken during the September 1999 run were not affected. The cause of the problem is unknown, although misalignment of the atmospheric-dispersion corrector is suspected. These have been traced and internal baffling has been installed. 1.5 nights commissioning time in 2000B are required.
Delivery is imminent.
A programme of enhancements to achieve this goal is under way. The 12 user feedbacks for 99B all rated the WHT's performance 'good' or 'excellent'. The noise is no longer present, but the cause of the problem is unknown. Steps are being taken to minimise noise when CCDs are changed over to the new SDSU controllers. A sensible default value has now been set, to reduce the likelihood of this happening again.