Most people already seened picture of their own or others and whenever they take a picture of the sun, a black dot appears over the sun..Reassure yourself..it aint a black hole or a planet whatsover.
Actually the black dot is called an CCD overexposure.
A digital camera has a electronic image sensor that converts light into an electronic signal. If an object is very bright, it can overwhelm the sensor. If you watch video shot with early digital video cameras, you'll see very bright lights show up on the recording as a bright vertical line. The engineers who designed cameras decided that wasn't a useful failure mode so they wrote instructions into the camera to shut off the pixels that got hit with the too bright light. Hence the black dot where the sun should be.
A very high intensity light could cause the bias on the capacitor.
An internet user named Jelfish had a comment on this on digg.com:
The way a digital camera works is that there is a photo-sensitive capacitor-array that captures information for each pixel. The amount of charge on a particular capacitor is proportional to the intensity of the light that hits it. So perhaps, because of the nature of the capacitors, a very high intensity light could cause the bias on the capacitor to surpass the breakdown voltage of the dielectric. This would cause the capacitor for that pixel to discharge and become neutral and therefore register no-light information ("black").
