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. We recommend using the 110mm lens, no binning, and slow readout speed for all data acquisition. Readnoise and gain (measured by E.G. April 2007) for each binning and readout mode is listed below.| Binning | Readout Speed | Gain (e-/DN) |
Readnoise (e-) | Readout Time (sec) |
Approx. Bias (DN) |
|---|---|---|---|---|---|
| x1 | slow | 1.2 | 8.0 | 11 | 1000 |
| x1 | fast | 1.2 | 14.6 | 3 | 1000 |
| x2 | slow | 1.2 | 8.8 | 3 | 1000 |
| x2 | fast | 1.3 | 17.1 | 1 | 1000 |
| x4 | slow | 1.2 | 8.9 | 1 | 1000 |
| x4 | fast | 1.3 | 16.7 | <1 | 1000 |