Recently Fujifilm released a medium format mirrorless digital single-lens camera called GFX 50S. Speaking of medium format, there is PENTAX 645 Z, a Japanese digital single lens reflex camera. Although it is anxious, the price is more expensive than the usual 35 mm full-frame machine, and hard to purchase. Another thing to worry about is the lens lineup. Whether there is a lens with the focal length that I frequently use. In order to confirm this, first of all, it is necessary to know in advance the focal length of a lens of medium format digital camera as to which focal length lens is the same as the focal length lens of 35 mm full size machine.
Sensor size and conversion formula
The following is the angle of view of the sensor size of each format and the lens focal length when converted to 35 mm full-frame.
In the case of GFX, 0.8 times the focal length of the lens is the same as the focal length of the 35 mm full-frame lens.
| Sensor size | Micro Four Thirds | APS-C（Canon） | APS-C | 35mm Full-Frame | Medium Format |
|---|---|---|---|---|---|
| Size | 17.3 x 13 | 22.5 x 15.0 | 23.6 x 15.8 | 36 x 24 | 44 x 33 |
| 35mm Full-Frame equivalent length | x2 | x1.6 | x1.5 | x1.0 | x0.8 |
GF lenses focal length and 35mm Full-Frame focal length relations
The following is the angle of view of the sensor size of each format and the lens focal length when converted to 35mm full-frame size.
| Lens | Focal length(mm) | 35mm Full-Frame equivalent(mm) |
|---|---|---|
| GF32-64mmF4 R LM WR | 32-64 | 25-51 |
| GF23mmF4 R LM WR | 23 | 18 |
| GF63mmF2.8 R WR | 63 | 50 |
| GF110mmF2 R LM WR | 110 | 87 |
| GF120mmF4 R LM OIS WR Macro | 120 | 95 |