How does the Rebels Self Cleaning Sensor Unit work?
Occasionally dust settles on the low-pass filter that sits in front of the Rebel’s CMOS sensor. To help eliminate the problem the Rebel XTi utilizes ultrasonic vibrations to ‘shake’ dust particles off the filter surface. These ultrasonic vibrations are set off every time the camera is turned on or off. To help prevent these same dust particles from resettling on the filter surface, strips of tacky material are strategically placed along the sides of the mirror chamber to trap lose particles and prevent them from causing further problems. In addition to ‘ultrasonic shakedowns’, the Digital Photo Professional (DPP) v 2.2 software (included with the Canon Rebel XTi) is able to plot the location of any stubborn dust particles that remain on the sensor, embed this information to the RAW or JPEG file, and electronically eliminate it in the final photos.
