Fujifilm X-Trans sensor


The Fujifilm X-Trans is a CMOS sensor developed by Fujifilm and used in its Fujifilm X-series cameras. Unlike most CMOS sensors featuring a conventional Bayer filter array, X-Trans sensors have a unique 6 by 6 pattern of photosites. Fujifilm claims that this layout can minimise moiré effects, and in turn increase resolution by eliminating the need for a low-pass filter.

Details

Typical Bayer sensor arrays have RGB photosites in a repeated 2 by 2 pattern. When it overlaps with a regular pattern that is being captured, a new interference pattern can occur that does not exist in real life. In contrast, X-Trans sensors have a more randomised pattern of RGB photosites than conventional Bayer array sensors, reducing the likelihood of interference and removing a need for a low-pass filter that lowers image resolution. See Patent PCT/JP2011/067419
Conventional Bayer sensors can also produce false colour as they do not have R and B photosites in some horizontal and vertical lines, Fujifilm claims that X-Trans sensors on the other hand have an improved colour reproduction due to all horizontal and vertical lines containing at least one R, G and B pixels.
Fuji claims that APS-C sized X-Trans sensors, while being physically smaller, have a greater perceived resolution than the number of pixels on the sensor and are said to be on par with some full frame sensors.
X-Trans sensors are said to be manufactured for Fujifilm by Sony Corporation.

Drawbacks

Software support

A drawback for users is the limited support of X-Trans sensors in third party raw processing software.
However, some open-source raw photo development programs support the X-Trans filter layout, and these include darktable and RawTherapee.

Image artifacts

Under certain conditions, cameras equipped with X-Trans II and III sensors can exhibit purple flare/grid artifacts in backlit photos. This occurs due to the particular arrangement of the phase detection and masking layers on the sensor. The appearance of the effect can vary with the demosaicing algorithms in use.

Future development

In an interview with DPreview during the CP+ 2017 show in Yokohama, Japan Fujifilm confirmed that an X-Trans sensor array is to be used for its next generation of APS-C sized sensors, whilst larger medium format sensors will continue using a conventional Bayer array because of the increased processing requirements of X-Trans filter arrangement.

List of X-Trans sensors

Sensor ModelNumber of effective pixelsTotal number of pixelsSensor sizeFirst announcement dateUtilizing cameras
X-Trans16.3 MP23.6 mm x 15.6 mm 9 January 2012Fujifilm X-Pro1
Fujifilm X-E1
Fujifilm X-M1
X-Trans II16.3 MP16.7 MP23.6 mm x 15.6 mm 7 January 2013Fujifilm X100S
Fujifilm X-E2
Fujifilm X-T1
Fujifilm X100T
Fujifilm X-T10
Fujifilm X-E2s
Fujifilm X70
X-Trans II12 MP14.5 MP2/3-inch7 January 2013Fujifilm X20
Fujifilm XQ1
Fujifilm X30
Fujifilm XQ2
X-Trans III24.3 MP23.6 mm x 15.6 mm 14 January 2016Fujifilm X-Pro2
Fujifilm X-T2
Fujifilm X100F
Fujifilm X-T20
Fujifilm X-E3
Fujifilm X-H1
X-Trans 426.1 MP23.5 mm x 15.6 mm 20 September 2018Fujifilm X-T3
Fujifilm X-T4
Fujifilm X-T30
Fujifilm X-Pro3
Fujifilm X100V