Detector

• Reset level jumps & dark current

  An upgrade to the NOTCam clock-board was made to shift the levels from 3.5V to their specified 5V level. The board was designed as a daughter board that interfaces directly to the existing clock-board. Two empty clock-boards were provided by CUO for this purpose.

  The results from testing the NOTCam new clock-boards is documented in

  http://www.not.iac.es/instruments/notcam/staff/clockboards/newclockboards.html
  

  and the main improvements were: 1) removal of shift-register glow, 2) removal of some horizontal stripes, 2) lower (8 e-) and more stable read-noise, especially notable for the reset-read-read mode. There was, however, no change in the behaviour of the number of counts in dark exposures as a function of integration time that was hoped for.

  The NOTCam calibration web page has been updated with new dark images.

• Bad pixels

  The improved determination of bad-pixel masks is an on-going project, but the evolution of the array in terms of the increased amount of cold pixels (from 0.2% to 0.4% of the array) over 2008 - 2009 is well documented on the NOTCam Calibration web page. See:

    http://www.not.iac.es/instruments/notcam/calibration.html
  

  and masks for `zero', `hot', and `cold' pixels are available for downloading. The archive is continuously updated to account for changes.

  The notcam.cl reduction package will be upgraded to improve handling of bad pixels.