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Direct Imaging with COSMIC at the Palomar 60-inch Telescope

It is possible to observe with COSMIC at the Cassegrain focus of the Palomar 60-inch telescope. In this setup, only the COSMIC CCD dewar, readout electronics, and computer (Sparc + PC) are used.

The filters are contained in the standard P60 CCD filter mounting base. There is a complete set of 3-inch filters for this use: UBVRIgriz. The filter motor is controlled by the VAX (username: CCD), not by the COSMIC computer. The standard filter motor commands are: FZERO (to zero the filter wheel, and change the filter names); FMOVE (to move to a new filter); and FSTAT (to display the current filter complement and setting).

The standard P60 offset guider is part of this setup.

The orientation of the COSMIC CCD in this configuration is non-standard, such that North points from the vertical. Rotation is possible using the Cassegrain mounting ring, but is difficult and many observers will choose to ignore this.

The COSMIC CCD and Palomar Observatory's CCD 13 are both high-QE, thinned,  pixel2 arrays that were produced in the same run, hence there is little difference between the sensitivities of the two arrays. The current electronics with COSMIC, however, have nearly twice the read-noise of CCD 13, hence for low-background applications (like U-band or narrow-band imaging) CCD 13 is the array of choice.


next up previous
Next: Warnings About COSMIC Up: User Manual for COSMIC Previous: Procedure for Aligning the
Roy Gal
4/25/1998