Commissioning of HiRAC at the Nordic Optical Telescope:
During January 8-16, 1996, the tip/tilt correcting adaptive optics camera HiRAC was succesfully commissioned at the NOT. The performance at the telescope is described.
Image quality at the Nordic Optical Telescope:
The image quality of the Nordic Optical Telescope is investigated by comparing image quality measurements from CCD data with simultaneous seeing data obtained with the nearby IAC seeing monitor. We find a difference between the seeing monitor and the image quality at the NOT of 0.25 +/- 0.05 arcseconds. We attempt to estimate the sources of aberration, and show that they may account for the difference. We conclude, that if the image quality of the telescope is optimized, a median image quality of approx. 0.4 arcseconds should be obtainable during the summer season, using tip/tilt correction.
HiRAC II, a 5-mode adaptive optics system for the NOT:
The performance of an upgraded HiRAC, correcting atmospheric defocus and astigmatism is estimated. Due to recent understanding of outer scale turbulence effects and factors degrading image quality at the NOT, better performance than initially estimated is found now. Design is briefly described and cost of implementation is estimated.
Washing CCD's:
Report on an attempt to remove oil contamination from the W11-4 CCD before re-installation in the DFOSC camera. Performance of the CCD before and after cleaning is compared, showing significant improvement by washing. The procedure for washing is described.