Last Updated 3 months ago
Definition
A 1?-type sensor refers to a video camera sensor format measuring approximately 13.2 × 8.8 mm, with a diagonal of about 15.9 mm. Despite the name, it is not actually one inch in size—a legacy naming convention carried over from the early days of television tube cameras.
This sensor type is common in compact digital cameras, camcorders, and broadcast video systems, striking a balance between image quality, lens versatility, and depth of field control.
Historical Background
The “inch-type” terminology originates from vacuum tube vidicon cameras used in the mid-20th century. The outer diameter of the imaging tube (not the active image area) was used as a measurement standard. A “1-inch” tube produced an image area roughly one-third smaller—about 13 mm × 9 mm—and that convention continues today, even though modern sensors are solid-state.
Thus, a 1? sensor in today’s digital cameras refers to the equivalent imaging area from that legacy standard, not a literal physical inch.
Technical Characteristics
- Approximate Dimensions: 13.2 mm (width) × 8.8 mm (height)
- Crop Factor: ~2.7× compared to full-frame 35 mm sensors
- Aspect Ratio: 3:2 or 16:9 depending on system
- Pixel Count: Typically 12–20 megapixels for stills or 4K resolution for video
Because of its smaller size compared to APS-C or full-frame sensors, a 1?-type sensor delivers greater depth of field and smaller lens designs, making it ideal for run-and-gun documentary, ENG (electronic news gathering), and compact cinema applications.
Advantages
- Portability: Enables smaller, lighter cameras and lenses.
- Extended Depth of Field: Useful for quick-focus or documentary shooting.
- Cost-Effective: Delivers strong image quality without full-frame expense.
- High Frame Rates: Easier data throughput allows faster readout for slow motion or high-speed video.
Limitations
- Reduced Low-Light Performance: Smaller pixels gather less light than larger sensors.
- Limited Shallow Focus: Harder to achieve extreme cinematic depth separation.
- Dynamic Range: Typically lower than Super 35 or full-frame sensors.
Common Examples
- Sony RX100 series (compact still/video hybrids)
- Sony Z90 / FX30 broadcast cams
- Canon XF705, Panasonic HC-X1, and similar ENG cameras
Related Terms
- [Super 35] ? Industry-standard motion picture sensor format (~24.9 × 18.7 mm).
- [Full-Frame Sensor] ? 35 mm-sized imaging area used in high-end digital cinema.
- [Crop Factor] ? Ratio comparing a sensor’s field of view to full frame.