Collection: Micro Four Thirds

The MFT format is much smaller than full-frame, but not always in reality. Here the OM 100-400mm f/5-6.3 IS lens (left) towers over the Canon RF 100-400 f/5.6-8 IS USM. However, the OM lens and MFT format with its 2x crop factor gives an equivalent 200-800mm.

MFT vs full-frame: the crop factor

The Micro Four Thirds format is based on a sensor size measuring 17.3x13mm, while the full-frame format is nominally 36x24mm.

The diagonal of MFT measures 21.6mm against 43.2mm for full-frame, so almost precisely double, which gives us the 2x crop factor that’s always mentioned in format comparisons.