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New iStar ICCD
Pre-Acquisition Setup - CCD
5.3.4.2 - Horizontal Pixel shift
Readout Rate
Horizontal pixel shift readout rate defines the rate at which pixels are read (or digitized) from the shift register. The faster
the horizontal readout rate the higher the frame rate that can be achieved. Slower readout rates will generate less noise
in the data as it is read out. The available rates are system dependant, and can be selected from a drop-down list on the
Setup Acquisition
dialog box, of which an example is shown below:
Pre-Amplifier Gain
Pre-amplifier gain determines the amount of gain applied to the video signal emerging from the CCD and allows the user
to control the sensitivity of the camera system. Depending on the system there are up to three options available. They
are again selected from a drop-down menu on the
Setup Acquisition
dialogue box:
These normalized gain settings will correspond to system sensitivities specified on the performance sheets (in terms of
electrons per A/D count) which accompany the system.
Selecting higher pre-amplifier gain values (i.e. x2 or x4) will increase the sensitivity of the camera (i.e. fewer electrons will
be required to produce one A/D count) and provide the lowest readout noise performance. However this may result in
the A/D converter saturating before the single pixel / register capacity of the CCD sensor is reached.
