Buying Gear

What is a Camera Sensor?

When deciding which digital camera to buy or use, it is critical to consider the sensor that comes with the camera because the image quality and the flexibility of what kinds of images you can capture is directly related to your camera’s sensor.

A camera sensor is a piece of hardware, a physical rectangle, inside the camera that captures light and converts it into signals in order to create an image.

Source: Expert photography

Sensors consist of millions of photosites, or light-sensitive spots that record what is being seen through the lens. The size of the camera’s sensor determines how much of this light is used to create the image.  As a result, if the camera sensor is large, more information can fit, producing better quality images wehn compared to smaller sensors. The size of the sensor also determines what you see through your camera’s viewfinder.

All digital cameras are classified by their sensor size, and the two most popular sizes are :

1. Full Frame

A Full-frame sesnor is the traditional 35mm film size.

An example Full frame sensor camera

2. The APSC (Advanced photo system type C)

A crop sensor is smaller than the standard 35mm sensor size, it is 22mm along its longest edge. This introduces a crop factor to the photos taken by these cameras. This means that the photo borders will be cropped in order to provide a narrower field of view.

An example of an APS-C (Crop) sensor camera

Effects Of Camera Sensor Sizes:

  1. Image quality and resolution
  2. Depth of field
  3. Angle of view
  4. Low-light performance
  5. Size of camera and lenses

Advantages of Full Frame camera:

  1. Image quality and dynamic range: Bigger sensors capture more details and information in the highlights and shadows of the images produced.
  2. Low light performance: A bigger sensor has bigger pixels which means each pixel can capture more light and this creates less noise at higher ISOs.
  3. Depth of field: Full frame sensors combined with wide apertures on lenses, help you capture very shallow depth of field especially when compared to APS-C.
  4. Field of view: A bigger sensor would help you capture a wider field of view when matched with a lens as the entirety of the sensor is used to create the images.
  5. Dynamic range: Bigger sensors capture more details and information in the highlights and shadows of the images produced.

Disadvantages of Full Frame camera:

  1. Size: Full frame sensor kits are a lot larger and heavier.
  2. Price: Full frame cameras, lenses and accessories for full frames are tyoically more expensive

Advantages of an APS-C camera:

  1. Size: In comparison to full frame cameras, APS-C cameras are a lot smaller and lighter.
  2. Longer focal length: Thanks to the crop, the same focal length on an APS-C camera will zoom in further than on a full frame camera. For example, a 50m on a full frame camera will produce an field of view of about 80mm on a crop sensor.
  3. Size: APS-C systems are typically cheaper than full frame cameras.

Disadvantages of an APS-C camera:

  1. Dynamic range: APS-C cameras capture less details in the highlights and shadows of the images produced.
  2. Low Light performance: Crop sensors typically perform worse at higher ISOs due to more noise.
  3. Depth of field: Due to the crop on the sensor, APS-C produce images with narrower depth of field when compared to full frame cameras.