Camera Sensor Size
The physical size of the light-catching chip inside a camera or phone, which shapes low-light quality, background blur and how big the whole kit is.
The sensor is the part of a camera that turns light into a picture. Its physical size shapes the picture more than most numbers in a specification. A larger sensor collects more light in each shot, so photos taken in dim places show less of the grainy speckle called noise. It also gives more background blur at the same framing.
Large sensor formats, from largest to smallest:
- Medium format: the largest in regular cameras.
- Full-frame: the size of a frame of classic 35 mm film.
- APS-C: a little under half the area of full-frame.
- Four Thirds: smaller again, which allows very compact bodies and lenses.
Small sensors in compact cameras, action cameras and phones carry inch labels such as 1-inch, 1/1.3-inch or 1/2.3-inch. These are old naming conventions, not real measurements. A larger fraction still means a larger sensor, so 1-inch is bigger than 1/1.3-inch, which is bigger than 1/2.3-inch.
What it does not promise
A bigger sensor does not guarantee a better photo, because the lens, focus, stabilisation and processing all play a part. Sensor size and megapixels are separate figures, so megapixels say nothing about how large the sensor is.