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CAMERA SENSOR TECHNOLOGY The difference between the sensor of a DSLR and a 3-chip camcorder is dramatic and is the basis of the difference in the performance of the two cameras. 3-chip camcorder sensors are very small in comparison to a DSLR sensor. The typical dimension of each sensor is about 1/3 inch across or 8 millimetres, and each chip has a resolution of about 2.2 mega pixels. These 3 tiny sensors are attached to a  precision color-separation beam-splitter glass prism that splits the incoming image light into the 3 RGB primary color images.  Therefore each chip is dedicated to only one color.  These 3 color signals are then combined by the camera electronics to form the video. A DSLR sensor is a large single chip with typical resolution of 16 mega pixels (or more) and a full-frame DSLR sensor is 43.3 mm across.  Each pixel on the sensor consists of 4 color filtered diodes, one blue, one red and 2 green. This is called the Bayer color filter array. Some cameras use other arrays but Bayer is the most common. The entire sensor is scanned top to bottom to generate an image frame.  Because HD resolution is much less than 16 mega pixels, the camera skips lines when recording video frames.  It is this line skipping technique that causes DSLR video recording issues like Moire  and Rolling Shutter. In addition there are 2 choices of sensor design either CCD or CMOS.  Most new cameras and all DSLRs are CMOS but some camcorders are CCD.  The CCD has some advantages in recording and it does not produce rolling shutter distortion.  CCD has disadvantages  including greater power consumption and vertical smear distortion.  For more details on these sensor types go here. In conclusion, all camera companies are working to improve their sensor technology and image processing engines.  In the future both rolling shutter and Moire distortions will be mostly resolved.
CAMERA SENSORS COMPARED

3-CHIP CAMCORDER SENSOR

DSLR FULL FRAME SENSOR

43.3mm
8mm
Beam Splitter Prism