An overview of Digital Cameras

Digital Cameras: What to look for when purchasing a digital camera for school use

What does a digital camera do

These cameras takepictures that can be downloaded to a computer These pictures can be emailed, posted on the Internet viewed on screen and stored on disk or CD and may be printed (special photographic paper can be used to improve quality of print outs).
Most digital cameras are generally auto focus and have  removable storage media; they have much in common with point and shoot cameras.

Features

Resolution: the detail that a camera can capture. This is measured in pixels. In
general 2 Megapixels is a good starting point and this resolution will allow
you to print out fairly decent A4 photographs. Photos for web and email can
be taken at lower resolutions. Look for at least  a2 to 3 megapixels camera.

Sensors: ccd sensors are used in most cameras apart from cheaper models

Storage medium on which shots are stored in the camera: 
  Smartmedia Cards: found in Fuji Cameras, 8,16,32, 64 MB
  Compact Flash: typical of Canon, size ranges up to 128 MB
  Memory Stick: typical of Sony cameras
  Floppy Disks: found in the beloved Sony Mavica 1.4 MB
High quality photos take up a lot of space; smart media cards are considered to be quite delicate and easy to damage.

LCD: this display is on the back of the camera and is used as a viewfinder,
check to see how it works in bright sunlight. These can used for reviewing
shots that have been taken. When conserving batteries they can be switched
off.
Lens: cheaper cameras have fixed focus and fixed zoom. Look for a lens with
autofocus and optical zoom (typical X3) ignore claims of digital zoom, that
can be done with software at a later stage.

 Interface with computer:
 USB is usual,  will not work on Windows 95 only Win 98 or above.
 Serial: older cameras have slow serial connections; will work with Windows  95
 Floppy Disk: works with any OS, can be transferred straight to
computer. If you take a lot of photos this can be very slow.

 Macro: This facility is needed for taking photos very close to the lens i.e.
project work
 Movies: some digital cameras have the facility to take short movies
(depending on the size of the memory card 16 MB: 5 mins) cheaper cameras
do not record sound just the moving images.
 Flash: Most cameras have a built in flash. Ensure that flash can be turned off.
Flash settings: Automatic, Forced flash, fill flash, no flash

Batteries: use rechargeable batteries. If AA NiMh rechargeable batteries are
used use at least 16000 mA batteries. It's a good idea to purchase a battery
charger. Cameras have a battery life of 1 to 3 hours solid use. More expensive
cameras use Lithium ion batteries which recharge quickly and hold their charge for longer.

Software: software is used to download images from the camera; you should
also check that image-editing software is supplied when you purchase your camera. Photoshop is the industry standard image editing but Paint Shop Pro is easy to use and will do all the editing that is needed. Have a look on the cover of computer magazines for free image editing software. Educational versions of Paint Shop Pro are available from suppliers such as diskovery:
Typical image editing activities are adjusting brightness and contrast, resizing image, cropping part of an image.

Guide to buying a digital camera:

1. 2 to 3 Megapixels is quite sufficient
2. Look for Optical Zoom and ignore Digital Zoom
3. Ensure Macro facility if using the camera for taking close up pictures
4. Large memory storage card (32 MB or greater) is essential
5.  Buy a charging unit and rechargeable batteries with spares
(minimum 1600 mAh)
6. Consider purchasing a mains adapter if the camera is going to
be used in the classroom
7. Look for bundled image editing software otherwise Paint Shop Pro is excellent and much cheaper and easier to learn than Adobe Photoshop but software is always down to a personal preference and Microsoft Photo Editor which is part of MS Office will do most of what is needed in the line of image editing.