The Digital Camera

1
The Digital Camera!

• By Michael Delaney

2
Breakthrough

• In the past 20 years, there have been many
  breakthroughs in technology but one of the most
  remarkable has been the Digital Camera.
• This is true because of the major difference
  between its past piece of technology,
  convectional cameras.

3
Convectional and Digital

• The Digital The Convectional

4
History

• The first ever digital camera for the consumer
  market was available for purchase on February
  17th, 1994.
• This camera was made by Apple and was called the
  Apple QuickTake 100 camera.

5
Apple QuickTake 100 camera
6
The sensors

• While convectional cameras have film, digital
  camera have a sensor.
• This sensor converts light into electrical
  charges.
• There are 2 types of sensors and they are the
  charge couple device (CCD) and the complementary
  metal oxide semiconductor (CMOS).

7
The sensors (continued)

• The easiest way to think of these sensors is a
  2-D array of millions of tiny solar cells.
• Once the light has changed into electrons by the
  sensors, it reads the value of each cell image.
• This is where you get the difference between both
  sensors.

8
Charge Couple Device (CCD)

• It transports the charge across the chip and
  reads it at the corner of the array.
• An analog-to-digital converter then turns each
  pixels value into a digital value.
• CCDs create high quality, low noise images.
• CCDs consume much more power than the CMOS,
  almost 100 times as much.
• Theyve been around for a longer time and tend to
  have higher quality pixels.

9
Complementary Metal Oxide Semiconductor (CMOS)

• These devices use many transistors at each pixel
  to amplify and move the charge using more
  traditional wires.
• Light sensitivity of a CMOS chip is lower.
• Consume very little power unlike the CCD.

10
Resolution

• Resolution is the amount of detail that the
  camera can capture.
• There are many type of resolution including
• 256x256- Very bad quality and has 65,000 pixels.
• 1216x912- A megapixel image size, 1, 109, 000
  total pixels.
• 2240x1680- On 4 megapixel cameras. Allows larger
  printed photos and is the current standard.
• The number of megapixels such as 3.1, means
  there should be at least 3, 100, 000 pixels.

11
Where does the color come from?

• The way to get a full color image, most sensors
  use filtering to look at the light in its 3
  primary colors, red, blue and green.
• There are many ways of recording these 3 colors
  in a digital camera.
• The best cameras use 3 separate sensors, each
  with a different filter.

12
Beam Splitter

• A beam splitters main purpose is to direct light
  to the different sensors.
• Each sensor gets the same look at the picture but
  because of the filters, each sensor only responds
  to one of the primary colors.
• The main advantage of this is the camera records
  each of the 3 colors at each pixel location.

13
Amount of Light

• A digital camera has to control the amount of
  light that reaches the sensor.
• The two components that control the amount of
  light are called the aperture and the shutter
  speed.

14
Aperture

• This is the size of the opening in the camera.
• Its automatic in most digital cameras but some
  allow manual adjustment to give professionals
  more control over the final image.

15
Shutter Speed

• This controls the amount of time that light can
  pass through the aperture.
• Unlike film, the light sensor in a digital camera
  can be reset electronically, so digital cameras
  have a digital shutter rather than a mechanical
  shutter.

16
Types of Lenses

• Digital cameras have 3 types of lenses.
• Optical-zoom lenses with automatic focus- These
  have wide and telephoto options and automatic
  focus. The camera might not use manual focus.
• Digital-zoom lenses- The camera takes pixels from
  the center of the image sensor to make them
  full-sized image.
• Replaceable lens systems- These are similar to
  the replaceable lenses on a 35mm camera. Some
  digital cameras can use 35mm camera lenses.

17
Storage

• Digital cameras use many different types of
  storage.
• Most digital cameras use fixed or removable flash
  memory.
• Other types of removable storage devices include
  floppy disks, hard disks, and writeable CDs and
  DVDs.

18
Data Compression

• One type that digital cameras use is repetition.
  If you take a picture of something and most of
  the picture is the same color, the same colors
  are going to be repeated so this takes out some
  of the color but this doesnt reduce the files
  anymore than 50 percent.
• The other type is irrelevancy. A digital camera
  detects more than the human eye can see, so, some
  compression routines throw away some of the more
  meaningless data.

19
Conclusion

• In conclusion, digital cameras have changed so
  much compared to the original film cameras. They
  are much easier to use and access. I believe
  digital cameras are just going to continue to get
  better and better!

20
References

• http//electronics.howstuffworks.com/digital-camer
  a.htm
• http//inventors.about.com/library/inventors/bldig
  italcamera.htm/
• http//www-users.mat.uni.torun.pl/olka/historia.h
  tml
• http//www.diversifiedimaging.net/canoncc.html
• http//www.physorg.com/newman/gfx/news/EasyShare-O
  ne.jpg
• http//images.apple.com/aperture/images/lens.jpg