Microtest Noise Pattern

There does appear to be a change in the images during the microtests. From the 2011-04-20 microtest, OTA36 row 6, and OTA47 row 5 and 6 show bright bands in the top ~6 pixels for the microtest19 setting. The following image shows OTA36/row6 with the default settings (top) and with SW_H changed by -1.0V (mt19, bottom):

The raw images show that this is not a result of the nonlinearity correction, as it is present before this is applied. It also is present in all rows of the detector, but is shorter on the other rows, and falls into previously masked regions. Image is of OTA36/xy66:

Similar patterns appear in other exposures on other OTA/row combinations. OTA66 seems to most commonly pick this up, as it is present on four out of nine exposures in the set (c5671g0017o,c5671g0020o,c5671g0022o,c5671g0024o). This last exposure (c5671g0024o) is back with the default voltages, which suggests that it is not the voltages that is causing the pattern, but the act of changing voltages.

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