CFH12K: Optimizing 12 MIT/LL CCID20 CCDs for a direct imaging application

CFH12K is a 12 k by 8 k wide field imaging camera for the CFHT prime focus. The mosaic consists of twelve MIT Lincoln laboratories 2 k by 4 k thinned backside illuminated CCID20 devices. The devices' operating parameters have been optimized to ensure the best data quality for use in broad and narrow band filter imaging mode. Adaptation to the CFHT prime focus environment included modifications to reduce the scattered light seen by the CFH12K. Science data taken by the camera has proven the success of CFHT's new capability for 42 by 28 arcmin(2) imaging with high resolution subarcsecond seeing.