The is a wide range of technology for our photographic sensors, and that is reflected in a multitude of options when it comes to buying our camera. But for now there is little variety and in the future perhaps enjoy organic sensors or Graphene, there are a few differences to keep in mind, especially in the Chambers of middle and low range which is where most marketing tricks are used to make a purchase.
CMOS sensor with Bayer-filter
First, we talked about CMOS sensors with your classic Bayer filter. This sensor is incorporating many cameras on the market but that they are gradually replacing with backlit sensors.
Classical sensors consist of a sensor that applies a chromatic pattern in which each photoreceptor is sensitive to a spectrum of wavelength specific RGB: one is red, the other blue and the other green. The amount of green photoreceptors is double red and blue because they are also those who are in charge of capturing the luminance of the picture.
The backlit sensor is a CMOS sensor with Bayer filter but with a substantial difference: the order of construction. This type of construction was developed and patented by Sony, so only computers that equipped a sensor built by the company will have these features.
Each traditional sensor is built in three layers. First there is the Bayer filter that makes every photoreceptor sensitive to a spectrum of wave visibe. Secondly, we found the transistors and the microcableado that directly affect the amount of light received by the third layer, composed of photodiodes collecting light.
Thus, with simply investing in the construction of traditional sensors, have sensors with increased sensitivity. Today almost all smartphones incorporate sensors manufactured by Sony that incorporate this technology. Also used in the range of sensors from Sony, including the new A7 II Sony and Sony A7R II, as well as the range of intermediate products.
That promises to be the paradigm shift from the photo sensor corresponds to the sensors, Foveon, a technology that ‘stacked’ color filters to stop making use of the Bayer filter. For now only Sigma has the patent for Foveon sensors, but soon many more manufacturers dare to experiment with these sensors trying to look for best results.
It is easier to see it in a picture to explain it, but putting it in words, we can say that the Bayer filter has a mosaic in which one of every four photoreceptors belong to a color, while two out of four, belong to green (one for luminance) and one for the color green. No one escapes that with this order, capture and color quality is seriously damaged and does not reproduce the tones as well as it should, or at least not in so much detail.
In this case, the Foveon stacked three layers: one sensitive to red, one blue and one green. Thus, rather than one of every four, or two of every four, each color has a complete layer sensitive to a spectrum of the visible wavelength.
Both the quality and the amount of detail from the color much larger samples, improving the clarity and color of our photos is triggered by the largest number of photoreceptors sensitive to different colors, which can perform calculations with a range.