SVS-Vistek evo1050 Operation Manual - page 42
6 Basic understanding of CCD Technology | 35
Cameras with a Dual-Tap output
can show image halves with different
characteristics, eg. different brightness.
Tap Balancing
In a quad-tap CCD (CCD with four outputs) the read out of the pixel
is four times faster than in a “normal” one.
An image generated by a dual-tap CCD can have differing brightness
between the two image halves. This is due to the requirement for a dual-
ADC circuit to handle the simultaneous digitisation of the two channels
of analog signal coming from the CCD. The fact that the two analog
output channels not being perfectly linear and the two output amplifiers
having physically different slopes leads to the necessity to sometimes
manually or automatically. adjust the gain levels of each channel indepen-
dantly to obtain a homogonous image.
Quad Tap Readout of CCD
“Quad Tap Output”