Specifications#
- Brand
- Casio
- Model
- GV-20
- Camera type
- Compact
- Sensor size
- 4.5 × 3.4 mm (1/3.2" sensor)
- Crop factor
- 7.69×
Specifications merged from Wikidata and openMVG. Spot an error? Tell us.
Sensor size compared#
Focal length equivalents & field of view#
Multiply any focal length by 7.69 to get the full-frame field of view. For fixed-lens cameras use the real focal length printed on the lens (e.g. “6.1–18.3 mm”), not the 35 mm equivalent.
| Lens on this camera | Full-frame equivalent | Horizontal | Vertical | Diagonal |
|---|---|---|---|---|
| 4 mm | 31 mm | 58.7° | 45.8° | 70.3° |
| 4.5 mm | 35 mm | 53.1° | 41.2° | 64.0° |
| 5 mm | 38 mm | 48.5° | 37.4° | 58.7° |
| 6 mm | 46 mm | 41.1° | 31.5° | 50.3° |
| 8 mm | 62 mm | 31.4° | 23.9° | 38.8° |
| 10 mm | 77 mm | 25.4° | 19.2° | 31.4° |
| 12 mm | 92 mm | 21.2° | 16.0° | 26.4° |
| 15 mm | 115 mm | 17.1° | 12.9° | 21.3° |
| 20 mm | 154 mm | 12.8° | 9.7° | 16.0° |
| 25 mm | 192 mm | 10.3° | 7.7° | 12.8° |
| 30 mm | 231 mm | 8.6° | 6.4° | 10.7° |
| 40 mm | 308 mm | 6.4° | 4.8° | 8.0° |
| 50 mm | 384 mm | 5.2° | 3.9° | 6.4° |
| 70 mm | 538 mm | 3.7° | 2.8° | 4.6° |
| 100 mm | 769 mm | 2.6° | 1.9° | 3.2° |
| 150 mm | 1153 mm | 1.7° | 1.3° | 2.1° |
Depth of field table#
Total depth of field at each subject distance, using a circle of confusion of 3.9 µm (the 0.030 mm full-frame standard scaled by the crop factor).
| Focal | Aperture | 50.0 cm | 1.00 m | 2.00 m | 3.00 m | 5.00 m | 10.0 m | Hyperfocal |
|---|---|---|---|---|---|---|---|---|
| 3 mm | f/2 | 52.9 cm | 6.85 m | ∞ | ∞ | ∞ | ∞ | 1.16 m |
| 3 mm | f/2.8 | 94.9 cm | ∞ | ∞ | ∞ | ∞ | ∞ | 82.7 cm |
| 3 mm | f/4 | 3.35 m | ∞ | ∞ | ∞ | ∞ | ∞ | 58.0 cm |
| 3 mm | f/8 | ∞ | ∞ | ∞ | ∞ | ∞ | ∞ | 29.1 cm |
| 6 mm | f/2 | 10.8 cm | 45.2 cm | 2.13 m | 6.73 m | ∞ | ∞ | 4.62 m |
| 6 mm | f/2.8 | 15.3 cm | 66.4 cm | 3.82 m | 31.3 m | ∞ | ∞ | 3.30 m |
| 6 mm | f/4 | 22.4 cm | 1.06 m | 13.7 m | ∞ | ∞ | ∞ | 2.31 m |
| 6 mm | f/8 | 52.5 cm | 6.71 m | ∞ | ∞ | ∞ | ∞ | 1.16 m |
| 10 mm | f/2 | 3.8 cm | 15.5 cm | 63.7 cm | 1.48 m | 4.59 m | 39.8 m | 12.8 m |
| 10 mm | f/2.8 | 5.4 cm | 21.9 cm | 91.3 cm | 2.19 m | 7.76 m | ∞ | 9.16 m |
| 10 mm | f/4 | 7.7 cm | 31.7 cm | 1.38 m | 3.58 m | 19.8 m | ∞ | 6.42 m |
| 10 mm | f/8 | 15.7 cm | 68.3 cm | 4.05 m | 43.5 m | ∞ | ∞ | 3.21 m |
| 17 mm | f/2 | 1.3 cm | 5.3 cm | 21.5 cm | 48.7 cm | 1.37 m | 5.81 m | 37.0 m |
| 17 mm | f/2.8 | 1.8 cm | 7.4 cm | 30.2 cm | 68.5 cm | 1.95 m | 8.80 m | 26.5 m |
| 17 mm | f/4 | 2.6 cm | 10.6 cm | 43.3 cm | 99.2 cm | 2.90 m | 15.2 m | 18.5 m |
| 17 mm | f/8 | 5.2 cm | 21.5 cm | 89.8 cm | 2.16 m | 7.58 m | ∞ | 9.27 m |
Equivalent aperture#
Exposure is identical at the same f-number on any format; equivalence only describes depth of field and total light.
Night-sky exposure limits#
Longest exposure before stars trail. The NPF rule accounts for pixel pitch and is stricter than the classic 500 rule — use it for pin-sharp stars on high-resolution sensors. (NPF needs a known resolution and is omitted here.)
| Focal length | 500 rule |
|---|---|
| 4 mm (31 mm eq.) | 16.3 s |
| 5 mm (38 mm eq.) | 13.0 s |
| 6 mm (46 mm eq.) | 10.8 s |
| 7 mm (54 mm eq.) | 9.3 s |
| 8 mm (62 mm eq.) | 8.1 s |
Handheld shutter speed guide#
The reciprocal rule uses the equivalent focal length. High-resolution sensors may need one stop faster than this for pixel-sharp results.
| Focal length | No stabilisation (1/equiv. focal) | With 3-stop IS | With 5-stop IBIS |
|---|---|---|---|
| 4 mm | 1/30 s | 1/4 s | 1 s |
| 7 mm | 1/50 s | 1/6 s | 0.6 s |
| 13 mm | 1/100 s | 1/13 s | 0.3 s |
| 26 mm | 1/200 s | 1/25 s | 1/6 s |
Lens#
The Casio GV-20 has a built-in, non-interchangeable lens. Use the real focal length of that lens with the tables above; its full-frame equivalent is that number × 7.69.
Similar cameras#
Other 1/3.2" cameras from around the same time.
Frequently asked questions#
What is the crop factor of the Casio GV-20?
The Casio GV-20 has a crop factor of 7.69× relative to 35 mm full frame (diagonal 5.6 mm vs 43.3 mm).
What size is the Casio GV-20 sensor?
4.5 × 3.4 mm (1/3.2"), an area of 15 mm² — 2% of full frame.
Is the Casio GV-20 full frame?
No — its sensor is 1/3.2", which is 56.8× smaller in area than full frame.
How long can I expose the night sky with the Casio GV-20?
With a 5 mm lens (38 mm equivalent) the 500 rule gives 13 s.
Sources & licences#
- Wikidata Q140489343 — CC0
- openMVG sensor width database — MPL-2.0
Last updated October 03, 2026 · How we calculate · Sources