We have always been outlined the doubt about the kindness of one or another system and although it is certain that some few years ago the technology on the sensors was quite more differenciated that now, the things have changed enough. Basically two types of sensors exist, on one hand the CCD (Charged Couple Device) and the other one the CMOS (Complementary Metal Oxidizes Semiconductor) and each one of them has their pluses and their bugs that will be more convenient in an or another application. Both models are in fact metal oxid semiconductors píxels and both of them accumulates a signal that is proportional to the intensity of light, but when the exposure has been completed really begins the differences: the CCD sends in a sequential way the information to the amplification section, where it transforms the loads into voltage and then to the camera electronics as you see in the image below:

In the CMOS the conversion loads - voltage (amplification) is carried out individually in each píxel and contrary to the CCD, the cells are completely standalone of their neighbors

Happily we could say that the CCD has bigger sensibility and therefore it is better to work with little light, so could say that CMOS doesn't affect the blooming (phenomenon that happens when a photo diode is boosted strongly in a CCD, it can infect to the near photo diode) and it solves well in status of strong light, or saying that has less noise and it is more economic in its construction, but if I must tell you the truth, with the enhancements that it has suffered the CMOS and the contínuos refinements of the CCD, nowadays is practically impossible to say that one is better than the other one. We can see that while Nikon and Canon use the CMOS technology in their top range cameras, as Nikon D3 or the Canon EOS 1, another markers so much or more prestigious in the photography world as can be Leica, Hasselblad or Phase One, use the CCD with high resolutions of 34 or more megapíxels in their Medium Format cameras . And more, I would dare to affirm that the camera firmware, the image engine processors, as it processes lights and shades, the RGB channels, etc. is much more influential in the final quality of the image independently that has a one type of sensor or another.