CFHT Information Bulletin Number 37, Semester 97II

The CFH12k Mosaic Camera

Timothy M. C. Abbott, CFHT (

To ensure CFHT's place as a prime site for high quality, wide field imaging, we are building a mosaic camera for use on the existing prime focus. This will serve as an interim wide-field imaging instrument while we wait for the construction of Megacam. It will contain twelve 2048x4096, 15 micron pixel CCDs, arranged in a 2x6 mosaic, resulting in a total imaging area measuring 8192 by 12288 pixels (
Figure 14).

The camera is being built in Gerry Luppino's lab at IfA in Honolulu according to a design derived from the UH8k camera which has already seen extensive service at CFHT. The biggest changes are the larger focal plane, a new shutter and second generation Leach/SDSU controllers. At the time of writing (July 1997), the dewar fabrication is almost complete, the focal plane design is under way, and the Leach controllers are on order.

The CCDs will be provided by Lincoln Laboratories, MIT. While these devices are still in production, early results are extremely encouraging, including the first device to show less than one electron per pixel readout noise using a conventional readout scheme, and an unmeasureable charge transfer inefficiency. The first four devices will be selected within 6 weeks.

Since PEGASUS is not capable of efficiently handling the data from such a large array, the instrument will be run using software developed in-house and based on the IfA/CFHT package used to run the UH8k mosaic array. Refinements may include the use of the MIT Parallel Virtual Machine (PVM) architecture and the NOAO Real Time Display (RTD) software (see article on GenX, page 25). Image files will be generated using the new NOAO mosaic FITS extensions.

First light for the CFH12k is anticipated late in semester 97II.

CFHT Information Bulletin Number 37, Semester 97II
Copyright © 1997, Canada-France-Hawaii Telescope