Digital Shift In 8 Bit Output Mode - Basler A400K User Manual

Basic Operation and Features

3.7.2 Digital Shift in 8 Bit Output Mode

No Shift
As mentioned in Section 3.1, the A400k uses 10 bit
ADCs to digitize the output from the CMOS sensor.
When the camera is operating in 8 bit output mode,
by default, it drops the least two significant bits
from the ADC and transmits the 8 most significant
bits (bit 9 through bit 2).
Shift Once
When the camera is set to shift once, the output
from the camera will include bit 8 through bit 1 from
the ADC.
The result of shifting once is that the output of the
camera is effectively doubled. For example,
assume that the camera is set for no shift, that it is
viewing a uniform white target and that under these
conditions the reading for the brightest pixel is 20. If
we changed the digital shift setting to shift once, the
reading would increase to 40.
If bit 9 is set to 1, all of the other bits will automatically be set to 1. This means that
you should only use the shift once setting when your pixel readings with no digital
shift are all below 128.
Shift Twice
When the camera is set to shift twice, the output
from the camera will include bit 7 through bit 0 from
the ADC.
The result of shifting twice is that the output of the
camera is effectively multiplied by four. For
example, assume that the camera is set for no shift,
that it is viewing a uniform white target, and that
under these conditions the reading for the brightest
pixel is 20. If we changed the digital shift setting to
shift twice, the reading would increase to 80.
If bit 9 or bit 8 is set to 1, all of the other bits will automatically be set to 1. This means
that you should only use the shift twice setting when your pixel readings with no dig-
ital shift are all below 64.
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DRAFT
Basler A400k