User's Guide to the Nickel Spectrograph

Table of Contents

Hardware Overview
Aperture Wheel
Filter Wheel
CCD Stage
Detector Characteristics
Software Overview
CCD User Interface
Motor Controller
Observing Hints
Calibration Lamp Spectra

Data Archive
Mt. Hamilton Homepage

Detector Characteristics

Currently a Reticon CCD (referred to as CCD-9 or Dewar#9) is the only detector available for the Nickel Spectrograph. Dewar#9 is a 400 x 1200 thinned array with 27 micron pixels. The detector is UV flooded to increase sensitivity and make the response more uniform.

Pixel scale is about 2 arcsec/pixel when using the 110mm lens (4 arcsec/pixel for 58mm lens). The field of view is approximately 3.6 x 3.6 arcminutes in direct imaging mode. The orientation in the image display window is North up and East to the right.

We recommend using the 110mm lens, no binning, and slow readout speed for all data acquisition.

Readnoise and gain for each binning and readout mode is listed below.

Readout Time
Linear to
x1slow0.68.0 1145,000
x1fast0.669 345,000
x2slow0.65.6 350,000
x2fastMode not usable, bias level > 25,000 DN.
x4slow0.77.6 150,000
x4fastMode not usable, bias level > 25,000 DN
Fast readout mode is not recommended for use.
Baseline bias should be about 1000 DN (unless otherwise noted).
Measured on telescope by E.Gates Sept 2010.

The CCD full well depth is 80,000 e-.

The CCD is read out using a single amplifier. The 32 column overscan region occupies the far right (highest numbered) columns.

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Last modified: Tue Jul 17 18:48:51 PDT 2012