Digital Cameras

Question 1

What do digital cameras consist of?

Answer 1

Lens that focuses light onto a sensor. Path of the light between the lens and sensor is regulated by a shutter

Question 2

What sensors are commonly used in digital cameras

Answer 2

CMOS (complementary metal oxide semiconductors)

CCD (Charge coupled device)

Both convert incident light into electrical charge

Question 3

How do digital cameras work?

Answer 3

Charge from sensors builds up in cells, each of which represents a pixel in the image.

Once photograph is taken, the charge in each cell is measured and converted into a digital value

Digital value is then processed by the camera and stored as a digital image

Question 4

How do colour cameras work?

Answer 4

There are multiple cells for each pixel, each of which has a filter that only allows certain wavelengths of light.

This allows the camera to build up a separate image for the intensity of each colour of light

Can then be combined to form a full colour photograph

Question 5

What is a Bayer filter?

Answer 5

A special colour filter used in digital cameras that has the same number of green filters and red and blue combined.

Using a Bayer filter produces an image that is a closer approximation of what the human eye sees