MDM Trouble Report for 2008 Apr 14

Telescope: 2.4m
Observer(s): McGreer (Columbia)
Instrument: TIFKAM

Problem(s) Encountered:
The extra noise is still present in the images, and in addition
the upper right quadrant is showing readout problems.  It has
a slightly different bias level and greater noise than the
rest of the chip.

The noise appears as a series of concentric flattened diamonds.
The fluctuations occur about every 10 pixels, and vary fairly
considerably between successive images.

In /lhome/data/biastest, I left some bias and dark frames where
the noise (including the bad quadrant) is clearly visible.
I also made a median bias that I smoothed over a scale of 15
pixels in order to remove the diamond pattern, and subtracted
this from the individual bias frames.  This isolates the
non-bias noise.  I left some of these images up in a ds9
window.

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Submitted on 2008 Apr 15 [5:26:56]