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Information on DQC plots and log

This document describes the DQC and log information available on the WFCAM Progress report page.

Summary Plots

The two plots on page one of the files use different colour codes for each filter:

  • J : blue
  • H : green
  • K : red
  • Y : black
  • Z : cyan

The plots on page two of the files use different colour codes for each chip:

  • Chip #1 : red
  • Chip #2 : green
  • Chip #3 : blue
  • Chip #4 : cyan

On each plot, there is one dot per data product (catalogue). The 5-sigma magnitude limits are computed for the output product frames for each MSB. Zeros for the seeing indicate no measure was possible and usually indicate a problem with the data for that detector.


Photometry Plots

The colour codes used in the plots shown in the are used to show the different filters and use the same convention descibed above for page 1 summary plots.
The points are the instrumental zero-points derived from 2MASS cross-matches (+colour equations) using for now a nominal extinction value of 0.05 in all bands. The dashed lines gives a rough reference of the expeceted photometric zero point for a perfectly photometric night. The open dots on the rightmost part of the plot show for each filter the mean zero point and the corresponding error bar (variation) for the whole night.
The open circles in the data points are ones where the measured seeing is worse than 2 arcsec or the stellar ellipticity is worse than 0.3, i.e. the images are severely trailed.

Observation log

The index files with the observation log for each night contain the following information:

  1. image name
  2. value of the PROJECT header keyword (Time-allocation code).
  3. value of the object keyword (Object name from telescope).
  5. value of the FILTER keyword (Filter name).
  6. value of the EXP_TIME keyword (Integration time per exposure [s]).
  7. value of the DATE-OBS keyword (Date time (UTC) of start of observation).
  8. value of the NJITTER keyword (Number of positions in telescope jitter pattern).
  9. value of the JITTER_I keyword (Serial number in this telescope jittern pattern).
  10. value of the NEXP keyword (Number of exposures in integration).
  11. value of the READMODE keyword (Name of the camera readmode).