Contents |
|
|
Digital Camera:
What is it?A digital camera is a device for taking still photographs by exposing charge-coupled devices (CCDs) or other light-sensitive electronics to light, and storing the resulting charges electronically. Digital cameras don't use film: they record images as electonic files which can be transferred to computers for direct processing or use. They can be printed using printers attached to computers, but by their nature they are best suited to viewing on computers...especially the Web.
Advantages
Digital cameras have a number of advantages over film when the goal is to put images on the Web...
Disadvantages
What's the conclusion...would you go film or digital?
Types of Digital Camera: ResolutionThere are two main distinctions between digital cameras: resolution and lensResolution
Resolution is the amount of detail that can be recorded. Like other computer devices, a camera's resolution is measured in pixels. A megapixel is 1,024,000 pixels and is used almost exclusively in describing digital cameras.
Remember the conventional wisdom that screen resolution is 72 pixels per inch (ppi) - or at least some relatively small number. A photo that's 1024 pixels wide will occupy more than the normal amount of space in most browser windows...but it will let you enlarge a part of the picture and see good details in it.
Lenses
No matter how many pixels a camera can capture, the image won't be good if the lens isn't good. While the price of electronic components has gone down steadily, the price of good lenses has stayed relatively stable. So really high-quality digital cameras are still very expensive!
Brands and GadgetsMajor brands of digital cameras:
Here's a list of the major digital camera manufacturers. Check them out on the Web!
Company Corporate URL Agfa http://www.agfa.com/ Canon http://www.canon.com/ Casio http://www.casio.com/ Epson http://www.epson.com/ Fuji http://www.fuji.co.jp/frame/f-00.htm Hewlett-Packard http://www.hp.com/ Kodak http://www.kodak.com/ Minolta http://www.minolta.com/open.html Nikon http://www.nikon.com/ Olympus http://www.olympus.com/ Panasonic http://www.panasonic.com/ Polaroid http://www.polaroid.com/ Sony http://www.sony.com/
Gadgets and Features
Here are some other features to look for:
- Type of memory
- Resolution modes (High Quality, Super-High...)
- LCD display
- How it can connect to the computer
- Size, weight, and ruggedness
- Optical zoom capability (preferable to digital zoom)
- Can lens be changed?
- Type of battery
- Video connection
Taking PicturesCheck Before you Start
Before you start taking pictures, here are some things to check:
- Are all the components at hand?
- Is there a storage device in the camera?
- Are the batteries in?
- How do you turn it on?
Turn it on and Check the Settings
- Is the battery fully charged (or reasonably full) ?
- What picture mode is it in (resolution)?
- Is it in closeup or panoramic mode?
- How many pictures can you take?
- If you're ready to fool around with it: light level, light quality, exposure time, etc. etc.
To Flash or Not to Flash
Flash photography is good if:
- Light level is very low - but digital cameras do a good job even in relatively low light
- Light is coming from behind the subject ("fill flash")
- Subject is moving and light level is relatively low
Flash can wash out subtile color differences, and can annoy people. It is sometimes prohibited in public displays.
LCD vs. Optical Viewfinder
The LCD panel on the back gives the best view of what the camera will really take a picture of, but it runs down the battery fairly fast.
Other Settings
Camera makers vie with one another to add features. You can usually take fairly good pictures without knowing them all, but if you have the time and the need to get the most out of the camera, spend some time with the instruction booklet. And remember - unlike film cameras, experimenting is free!
Point and Shoot...Carefully
- Depress the trigger half-way. This allows the camera to autofocus and measure light level. Check for an indicator of light level: does it think it needs the flash?
- Align the camera carefully with straight lines. You can rotate the image later, but it's a lot quicker to get it right the first time!
- Squeeze the trigger very slowly. One of the most frequent causes of poor pictures is the jerk pushing the button. ;-)
- Allow the camera a couple of seconds to save the image. There is probably an indicator showing when it's ready to shoot again.
Transferring Images to ComputersThe main methods of getting images from the camera to the computer are diskette, serial cable, and memory card reader.
Diskette
A few cameras - noteably Sonys - use diskettes. The newest Sony models can burn CDrw's.
Serial cable
Connecting from a special plug in the camera to the 9-pin serial port at the back of the computer.
Memory card reader
There are three major types of memory cards: Smart Media, Flash Memory, and Memory Stick. Each requires a different type of reading device, but most plug into a computer's USB port. These are the quickest. Some have a special device that goes into the floppy disk drive.
Prepping Digital Photos for the
Web What do you need to do?
You really don't need to do anything! The JPEG format used by most cameras will go right to a Web server, ready to use.
Cropping
Newer digital cameras capture more pixels than can be displayed in most Web browser windows. Also, most pictures (except landscapes) tend to have more in them than you want, so cropping is almost always helpful.
Adjusting
Brightness, contrast, color, and alignment often need to be adjusted, even if you don't want "special effects" in the picture.
Including Digital Photos on your
Project Use the pictures you've taken for the Web page you're building as part of your project (module D45h). Include at least two pictures you've taken yourself.
Audience: This is for people who are familiar with
Web graphics in general and want to learn how to use digital cameras to produce
Web images.
Objectives: When you successfully complete
this lesson, you will be able to...
About this document...
Module D42h: This
document is part of a modular instruction series in computer technology. For
more information, see the overview
or the list of modules in this series, D: Desktop Publishing
and Computer Graphics. This document has been used in the following classes:
INP 143.