2. Pixels
 A Pixel or pel in digital imaging is a physical point in a Rasta image
 In a display device its is the smallest addressable element
 The pixel address corresponds to its physical coordination
 Each pixel is a sample of an original image
 Each pixel intensity is variable

3. Pixels
 Picture element is what the term pixel actually stands for.
 The way they make up the images on digital is by using all these little tiny
dots.
 A matrix of maybe millions of pixels is divided up on screen.
 Even though pixels can only make one colour at a time they often mix
together to make various shades.
 The number of bits used to represent it will determine how many colours
a pixel can be,

4. Colour and pixels
 The number of bits per pixel that can be displayed on a computer screen is what
defines colour depth
colour depth No of colours
1 bit colour 2
4 bit colour 16
8 bit colour 256
24 bit colour true colour
 More colours can be displayed the more bits each pixel has
 The examples of this are shown above

5. Cameras – converting light
 Digital cameras have a sensor that converts light into electric charges
 This is clearly about alternative then film

6. Cameras – converting light
 Digital cameras a far more advanced then film
 They convert light into electrical charges via a sensor
 In the camera there is a sensor made out of silicon
 A digital camera using the lens takes light and puts it on to the sensor
 Each photo site on the sensor absorbs photons
 It also releases electrons trough the photoelectric effect
 Electrons are emitted from matter in the photo electric effect

7. Cameras – converting light
 A charge coupled device is the image sensor deployed by most typical
cameras
 Some different cameras use alternative technology like complementary
metal oxide semiconductor
 They both are shortened down as ccd or cmos
 Ccd and cmos bothe convert light into electrons