Sony RX100 series crop factor: 2.73×
Every Sony RX100 from the original to the VII uses a 1-inch type sensor of 13.2 × 8.8 mm: a 2.73× crop factor behind three different fixed zoom lenses. Its 13.2 × 8.8 mm sensor has a 15.86 mm diagonal, so lenses frame 2.73× tighter than on full frame.
A 8.8 mm lens on 1-inch (2.73× crop) frames like a 24 mm lens on full frame. At f/1.8 it gives the depth of field of about f/4.9 there — but exposure stays the same as f/1.8.
- Horizontal field of view
- 73.7°
- Vertical field of view
- 53.1°
- Crop ratio
- 2.73×
- Sensor size
- 13.2 × 8.8 mm
Full-frame equivalent of a 8.8 mm f/1.8 lens on each format
| Sensor | Focal length | Aperture (DoF) |
|---|---|---|
| Full frame | 9 mm | f/1.8 |
| APS-C (1.5×) | 13 mm | f/2.8 |
| Canon APS-C (1.6×) | 14 mm | f/2.9 |
| Micro Four Thirds | 18 mm | f/3.6 |
| 1-inch | 24 mm | f/4.9 |
| Medium format (44×33) | 7 mm | f/1.4 |
| Phone main camera (1/1.3″) | 31 mm | f/6.3 |
Sensor size and crop factor
Crop factor is the full-frame diagonal (43.27 mm) divided by the sensor diagonal. For the RX100: √(13.2² + 8.8²) = 15.86 mm, and 43.27 ÷ 15.86 = 2.73.
| Property | Value |
|---|---|
| Sensor size | 13.2 × 8.8 mm |
| Diagonal | 15.86 mm |
| Crop factor (computed) | 2.73× |
| Crop factor quoted by the maker | 2.7× |
| Area vs full frame | 13% |
| Circle of confusion (diagonal ÷ 1443) | 0.011 mm |
| Resolution / pixel pitch | 20.1 MP · 2.40 µm |
| Lens mount | fixed lens |
Source: Sony specifications (RX100 VII): 1.0-type (13.2 × 8.8 mm) Exmor RS CMOS sensor; ZEISS Vario-Sonnar T* 9.0–72 mm F2.8–4.5 lens (24–200 mm equivalent).
Equivalent focal length and aperture for each RX100 lens
The full-frame equivalent is the focal length × 2.73. The DoF-equivalent aperture (f-number × 2.73) describes depth of field and total light at the same framing; exposure — shutter speed and ISO — is set by the real f-number as usual. Hyperfocal distances use a 0.011 mm circle of confusion.
| Lens | Focal length | Full-frame equivalent | Max aperture | DoF-equivalent aperture | Horizontal view | Hyperfocal at f/8 |
|---|---|---|---|---|---|---|
| RX100 and RX100 II (10.4–37.1mm F1.8–4.9)at 10.4 mm | 10.4 mm | 28.4 mm | f/1.8 | f/4.9 | 64.8° | 1.24 m4.07 ft |
| RX100 and RX100 II (10.4–37.1mm F1.8–4.9)at 37.1 mm | 37.1 mm | 101 mm | f/4.9 | f/13.4 | 20.2° | 15.7 m51.4 ft |
| RX100 III, IV, V and VA (8.8–25.7mm F1.8–2.8)at 8.8 mm | 8.8 mm | 24.0 mm | f/1.8 | f/4.9 | 73.7° | 89 cm2.92 ft |
| RX100 III, IV, V and VA (8.8–25.7mm F1.8–2.8)at 25.7 mm | 25.7 mm | 70.2 mm | f/2.8 | f/7.6 | 28.8° | 7.53 m24.7 ft |
| RX100 VI and VII (9.0–72mm F2.8–4.5)at 9 mm | 9 mm | 24.6 mm | f/2.8 | f/7.6 | 72.5° | 93 cm3.05 ft |
| RX100 VI and VII (9.0–72mm F2.8–4.5)at 72 mm | 72 mm | 197 mm | f/4.5 | f/12.3 | 10.5° | 59.0 m194 ft |
What is different about the RX100
A "1-inch" sensor is not an inch across. The name is a holdover from video camera tubes, where a 1-inch tube had an image area of about 16 mm diagonal. The RX100 sensor’s real diagonal is 15.9 mm, giving a crop factor of 2.73×; Sony rounds it to 2.7× when it quotes 24 mm or 28 mm equivalents.
Because the lens is fixed, the useful question is what each model’s zoom is equivalent to. The f/1.8 aperture of the 24–70 mm models (III to VA) sounds very fast, but its depth of field matches about f/4.9 on full frame at 24 mm and f/7.6 at 70 mm. That is why RX100 photos are sharp from near to far, and why background blur needs a close subject at the long end. The VI and VII trade that brightness for reach to a 197 mm equivalent field of view.
FAQ
What is the crop factor of the Sony RX100 series?
2.73×. The 13.2 × 8.8 mm sensor has a 15.86 mm diagonal, and 43.27 ÷ 15.86 = 2.73. The maker rounds it to 2.7×.
What is the full-frame equivalent of the RX100 III–VA lens (8.8–25.7mm F1.8–2.8)?
24–70 mm in field of view, with the depth of field of about f/4.9–f/7.6 on full frame. Exposure does not change: f/1.8 still needs the same shutter speed and ISO as f/1.8 on any camera.
Why does Sony say 24–70 mm when the lens says 8.8–25.7 mm?
Sony quotes the 35 mm-equivalent field of view. Multiplying by the 2.73× crop factor gives 24.0 and 70.2 mm, which Sony rounds to 24–70 mm. The real focal length, printed on the lens and recorded in the EXIF data, is 8.8–25.7 mm.
Other cameras
- Sony a640023.5 × 15.6 mm · 1.53× crop
- Sony a670023.3 × 15.5 mm · 1.55× crop
- Sony ZV-E1023.5 × 15.6 mm · 1.53× crop
- Canon EOS R5022.3 × 14.9 mm · 1.61× crop
- Canon EOS R1022.3 × 14.9 mm · 1.61× crop
- Nikon Z5023.5 × 15.7 mm · 1.53× crop
- Fujifilm X-T523.5 × 15.6 mm · 1.53× crop
- Panasonic Lumix G9 II17.3 × 13 mm · 2.00× crop
- iPhone 17 Pro main camera≈ 10.0 × 7.5 mm · 3.46× crop
More on the 1-inch format — depth of field, hyperfocal and star charts — on the 1-inch sensor page. The theory is in crop factor explained.