Blooming is an effect that usually occurs with older, digital cameras with CCD sensors. Light points and stripes on the image are common for this effect. These are caused by overexposed areas, as the sensor’s pixels are only able to absorb a certain amount of charge. The excess amount of charge is released to neighboring pixels, creating a bright spot in the form of a stripe.
The white stripe below the sun is a result of the bloomig effect. On the other hand, the roundish white spot around the sun is caused by scattering of light in the atmosphere and optics and has nothing to do with blooming.
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What can you do about it? So-called anti-blooming gates can be installed in the sensor, which release excess charge. However, this reduces the sensitivity due to the larger pixel size. Long exposure times can result in overexposure, as the charge will drain before a storage cell is full. CCD sensors are therefore rarely provided with these gates, as they are often used for light-sensitive pictures.