camera sensors explained why size matters
Camera light sensors are like the ‘films’ of digital cameras. They consist of millions of light sensitive ‘Photosites’ which capture the light reflected on them and convert them into digital images. The larger the film, the more light is captured; consequently producing sharper images with more details. This enables the camera to shoot even in low light, keeping the noise and aberrations low, and also giving a better low lighting performance.
The following camera sensor size comparison chart illustrates the relative sizes of different camera sensors.
On a given camera light sensor, the more the pixels, the smaller the pixels will be. So if we have, say the same sized sensor on a 20MP camera, it will have smaller sized pixels than an 18MP camera. An 8MP camera with larger sensors will produce better quality images than a 12MP camera with smaller sensors. This is the reason why DSLRs of the same number of megapixels will produce much better colour composed images than a smart phone with the same number of megapixels due to much larger sized camera sensors in DLSR compared to the smart phone camera sensor size.
- Full frame (36mm by 24mm): This is the largest sensor size available and has the same size as a frame of 35mm film. Even though it is the oldest format, it remains the industry standard even today.
- APS-C (23.6mm by 15.8mm): It is almost half the size of a full frame sensor, and is the most popularly used camera sensor size in DSLR manufactured by brands like Canon, Nikon, Pentax, and Sony, where the sizes may marginally vary from brand to brand. It is also called the ‘Crop sensor’ as its sensor crops out the edges of the frame, increasing the effective focal length of a mounted lens by a crop factor of 1.5x
- Four Thirds (17.3mm by 13mm): It is a relatively newer format, roughly a quarter of the size of a full-frame sensor. This makes the camera body lighter, affordable and easy to carry around. It has a 2x crop factor which doubles the effective focal length.
Digital cameras today majorly use two main types of sensors;
- CCD (charge-coupled device): The older type of the two, CCD sensor captures light photos as electrical charges in each light-sensitive area that represents a pixel, and converts the analogue data into digital image data.
- CMOS (complementary metal-oxide semiconductor): In the CMOS sensor, every photo site can be accessed individually. The sensor can manipulate the data for each pixel right in the sensor and respond to lighting conditions in ways that a CCD can’t.
For more info visit our Camera Buying guide