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Cross-talk

In dual read-out mode, cross-talk occurs between the two amplifiers. An image of a star in one side of the image will then have a fainter electronic ghost image mirrored around the border of the two image sections.

A pin-hole was imaged in channel A, at an illumination level of approx. 60000ADU, low gain. The image was seen in the B channel, reduced by a factor of 20000.

This means that the ghost image of a bright source will easily be detected, and one should consider carefully whether dual readout is compatible with the planned observations.



Tim Abbott
Mon Apr 12 17:00:34 ACT 1999