Fujifilm X-Trans Artifacts
There seems to be a lot of misinformation on the web regarding the cause (and cure) for the fractal artifacts that affect some images captured with Fujifilm's X-Trans sensor cameras. The problem stems from the inability of some image processing software, notably products from Adobe such as Lightroom and Photoshop, to correctly interpolate the RAW data due to Fujifilm's use of a non-Bayer colour filter array over the image sensor.
This is an image captured with a Fujifilm X-T3 camera and processed in Lightroom:
|Fujifilm X-T3, XF 10-24mm f4 @ 24mm, 1/210 sec @ f5.6, ISO 160|
At first glance, the image looks quite nice; sharp, and with lots of rich colour the Fujifilm cameras are noted for. However, on closer inspection, the fine details in the image, such as the pebbles on the beach, look strange and distorted:
|100% crop of above image|
At the limited upload size, it may be difficult to discern the artifacts, so here is a 200% crop of the same image:
Now the fractal artifacts are clearly visible, with the smooth round pebbles taking on a "wormy"appearance, with jagged edges and strange elongated proportions. A popular "cure" for this issue is the set the Details slider to zero in the Lightroom sharpening panel: