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Quality Control and
Data Processing

CAL | HC | refs | QC
   Parasitic Dark
Solar&sky spectra
QC links:
UVES: Dark
Parasitic Light
QC1 database (advanced users): browse | plot

In addition to the regular DARKs, there are also open-shutter DARKs (CATG = CALIB, TYPE = PARASITIC, TECH = IMAGE). They include, in addition to the CCD dark current, contribution from the camera enclosure. It most likely originates from Cerenkov radiation due to radioactive decay. These DARKs are regularly taken to monitor all kinds of parasitic light in the dome.

These data thus give detailed charateristics for all THREE UVES CCDs, one BLUE and two RED (UPPER and LOWER).

Parasitic Darks parameters


FITS key QC1 database: table, name definition class* HC_plot** more docu
[calculated by QC procedure] uves_dark..current_dark mean_dark, normalized to 3600 secs exposure time HC [docuSys coming]
[calculated by QC procedure] uves_dark..mean_raw mean value of raw frame CAL [docuSys coming]
[calculated by QC procedure] uves_dark..mean_dark mean value across master dark CAL [docuSys coming]
*Class: KPI - instrument performance; HC - instrument health; CAL - calibration quality; ENG - engineering parameter
**There might be more than one.


These frames are taken approximately once per month, as a set of 3 consecutive exposures of 3600 secs each. These data are de-biased and combined into a MASTER_DARK, in which the average dark level is measured (in ADU/px/hr).

You can also see here basic QC parameters related to detector properties (like median level, ReadOut Noise, etc).

Scoring&thresholds Parasitic Darks parameters

The thresholds are set as an offset around the median. The user manual gives an indication of the values. These are given in e-/pix/h (ADU/pix/h) at -120C:


The trending of the Parasitic Light DARK during the life time of the instrument is best be seen with the full history PDARK trending plots shown here: FULL DARK history.

Algorithm Parasitic Darks parameters

All the parameters are calculated by a QC script

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