Panasonic Lumix G9 II crop factor: 2.00×
The Lumix G9 II is Panasonic’s flagship Micro Four Thirds stills camera. Like every MFT body, including the OM System OM-1 and OM-5, it has an almost exact 2× crop factor. Its 17.3 × 13 mm sensor has a 21.64 mm diagonal, so lenses frame 2.00× tighter than on full frame.
A 45 mm lens on Micro Four Thirds (2× crop) frames like a 90 mm lens on full frame. At f/1.8 it gives the depth of field of about f/3.6 there — but exposure stays the same as f/1.8.
- Horizontal field of view
- 21.8°
- Vertical field of view
- 16.4°
- Crop ratio
- 2.00×
- Sensor size
- 17.3 × 13 mm
Full-frame equivalent of a 45 mm f/1.8 lens on each format
| Sensor | Focal length | Aperture (DoF) |
|---|---|---|
| Full frame | 45 mm | f/1.8 |
| APS-C (1.5×) | 69 mm | f/2.8 |
| Canon APS-C (1.6×) | 72 mm | f/2.9 |
| Micro Four Thirds | 90 mm | f/3.6 |
| 1-inch | 123 mm | f/4.9 |
| Medium format (44×33) | 36 mm | f/1.4 |
| Phone main camera (1/1.3″) | 158 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 G9 II: √(17.3² + 13²) = 21.64 mm, and 43.27 ÷ 21.64 = 2.00.
| Property | Value |
|---|---|
| Sensor size | 17.3 × 13 mm |
| Diagonal | 21.64 mm |
| Crop factor (computed) | 2.00× |
| Crop factor quoted by the maker | 2× |
| Area vs full frame | 26% |
| Circle of confusion (diagonal ÷ 1443) | 0.015 mm |
| Resolution / pixel pitch | 25.2 MP · 2.99 µm |
| Lens mount | Micro Four Thirds |
Source: Panasonic specifications: 4/3-type Live MOS sensor, 17.3 × 13.0 mm, 25.21 million effective pixels. The OM System OM-1 and OM-5 use the same Four Thirds format (published as 17.3–17.4 × 13.0 mm).
Equivalent focal length and aperture for Micro Four Thirds lenses
The full-frame equivalent is the focal length × 2.00. The DoF-equivalent aperture (f-number × 2.00) 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 0.015 mm circle of confusion.
| Lens | Focal length | Full-frame equivalent | Max aperture | DoF-equivalent aperture | Horizontal view | Hyperfocal at f/8 |
|---|---|---|---|---|---|---|
| Lumix G Vario 12–60mm F3.5–5.6 (kit)at 12 mm | 12 mm | 24.0 mm | f/3.5 | f/7.0 | 71.6° | 1.21 m3.98 ft |
| Lumix G Vario 12–60mm F3.5–5.6 (kit)at 60 mm | 60 mm | 120 mm | f/5.6 | f/11.2 | 16.4° | 30.1 m98.6 ft |
| Leica DG Vario-Elmarit 12–60mm F2.8–4 (kit)at 12 mm | 12 mm | 24.0 mm | f/2.8 | f/5.6 | 71.6° | 1.21 m3.98 ft |
| Leica DG Vario-Elmarit 12–60mm F2.8–4 (kit)at 60 mm | 60 mm | 120 mm | f/4 | f/8.0 | 16.4° | 30.1 m98.6 ft |
| Leica DG Summilux 9mm F1.7 | 9 mm | 18.0 mm | f/1.7 | f/3.4 | 87.7° | 68 cm2.24 ft |
| OM System M.Zuiko 17mm F1.8 | 17 mm | 34.0 mm | f/1.8 | f/3.6 | 53.9° | 2.43 m7.96 ft |
| Lumix G 25mm F1.7 | 25 mm | 50.0 mm | f/1.7 | f/3.4 | 38.2° | 5.23 m17.2 ft |
| Leica DG Nocticron 42.5mm F1.2 | 42.5 mm | 85.0 mm | f/1.2 | f/2.4 | 23.0° | 15.1 m49.5 ft |
| OM System M.Zuiko 45mm F1.8 | 45 mm | 90.0 mm | f/1.8 | f/3.6 | 21.8° | 16.9 m55.5 ft |
| Leica DG Vario-Elmar 100–400mm F4–6.3at 100 mm | 100 mm | 200 mm | f/4 | f/8.0 | 9.9° | 83.4 m274 ft |
| Leica DG Vario-Elmar 100–400mm F4–6.3at 400 mm | 400 mm | 800 mm | f/6.3 | f/12.6 | 2.5° | 1,334 m4,376 ft |
What is different about the G9 II
A 17.3 × 13.0 mm sensor has a 21.64 mm diagonal — almost exactly half of full frame’s 43.27 mm — so the crop factor is 2.00×. That makes Micro Four Thirds the easiest system for mental arithmetic: double the focal length for framing, and double the f-number for depth of field and total light. The OM-5’s sensor is published as 17.3 or 17.4 mm wide depending on the source; at 17.4 mm the crop is 1.99×, the same in practice.
What is different is the shape. Micro Four Thirds is 4:3, not 3:2, so the diagonal crop factor hides two others: the width is 36 ÷ 17.3 = 2.08× narrower than full frame, while the height is only 24 ÷ 13 = 1.85× smaller. Shoot in 3:2 to match full-frame framing and the effective crop rises to about 2.08×. The upside is reach: the Leica 100–400mm frames like a 200–800 mm lens, which is why the G9 II and OM System bodies are so popular for birds.
FAQ
What is the crop factor of the Panasonic Lumix G9 II?
2.00×. The 17.3 × 13 mm sensor has a 21.64 mm diagonal, and 43.27 ÷ 21.64 = 2.00. The maker rounds it to 2×.
What is the full-frame equivalent of the Lumix G Vario 12–60mm F3.5–5.6?
24–120 mm in field of view, with the depth of field of about f/7.0–f/11.2 on full frame. Exposure does not change: f/3.5 still needs the same shutter speed and ISO as f/3.5 on any camera.
What does the Leica DG Nocticron 42.5mm F1.2 equal on full frame?
About 85 mm f/2.4: the field of view of a 85 mm lens and the depth of field of f/2.4 on full frame. Its hyperfocal distance at f/8 on the G9 II is 15.1 m (49.5 ft).
Is Micro Four Thirds exactly 2× crop?
By the diagonal, yes: 43.27 ÷ 21.64 = 2.00 for a 17.3 × 13.0 mm sensor. Because the format is 4:3 rather than 3:2, the horizontal crop is about 2.08× and the vertical about 1.85×, so a 3:2 crop from an MFT file frames like a lens 2.08× longer on full frame.
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
- Sony RX100 series13.2 × 8.8 mm · 2.73× crop
- iPhone 17 Pro main camera≈ 10.0 × 7.5 mm · 3.46× crop
More on the Micro Four Thirds format — depth of field, hyperfocal and star charts — on the Micro Four Thirds sensor page. The theory is in crop factor explained.