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2 Camera Basics
25
Micro lenses with CRA correction
Some sensors have micro lenses offset to the sensor edge. They compensate for shading created by obliquely
incident light. The angle of incident light is called Chief Ray Angle (CRA), the micro lens offset is thus called CRA
correction. The amount of micro lens shift is specified in degrees and refers to the micro lenses in the corners of
the sensor.
Micro lenses without CRA correction
Image captured without CRA correction shows
shading
Micro lenses with CRA correction
Image captured with CRA correction
Note
Using parallel light on sensors with CRA correction may cause slight color variations. These may occur, for
example, if telecentric lenses are used. The following models are equipped with sensors with offset micro lenses:
DCC1240x/DCC3240x
DCC1645C
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