The Fujifilm GFX 100 is a mirrorless camera with a 102 megapixel, 43.8mm x 32.9mm medium-format back illuminated CMOS sensor with phase detection pixels.

This sensor is approximately 1.7x larger than the one found in a 35mm full frame camera, and is the first ever back illuminated sensor with phase detection pixels to appear in a medium format camera. The main benefit is much improved autofocusing speed, claimed to be up to twice as fast as previous GFX models.
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