3) Image Sensor
At the heart of the X-Pro1 sits an X-Trans CMOS sensor technology from Fuji. While traditional sensors with a repeating bayer-pattern color filter array exhibit moire problems and hence need an anti-aliasing filter to reduce moire by essentially blurring the image, the X-Trans CMOS sensor has a new color filter array that has a more random pattern that does not cause moire to occur in first place. Hence, an anti-aliasing filter is not necessary, which in turn translates to sharper, more detailed images.
Here is an illustration of a traditional bayer pattern color filter array compared to the new Fuji color filter array:
Top image: 1) Lens, 2) Sensor, 3) Optical low-pass filter.
Bottom image: 1) Lens, 2) Sensor, 3) Natural random arrangement of the fine grains of silver halide in film.
As you can see, the difference between the two is quite big.
Fuji says that their sensor not only delivers sharper images due to the lack of an anti-aliasing filter, but also has better color reproduction. Does the new X-Trans CMOS sensor work as advertised? It certainly does, in my opinion. The amount of detail from the camera when using the Fujinon 35mm and 60mm lenses (more on lenses below) is impressive when looking at images at 100%. And as I have already written before, the colors from the Fuji are simply outstanding. As a long time digital Nikon shooter, I am very impressed by what the X-Pro1 does with the colors. Not only does the camera produce beautiful colors, but Fuji clearly knows how to process skin tones – something Nikon is historically not very good at. This is quite evident even when looking at JPEG images straight out of the camera.
The X-Trans CMOS sensor with a new color filter is a great innovation. Sadly, most digital camera manufacturers today, including Nikon and Canon, still rely on the bayer pattern that was invented back in 1976 in Kodak labs. With all the new ultra high resolution sensors coming out, I believe manufacturers need to start adopting such innovations to get rid of the outdated anti-aliasing/blur filter.