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Megapixels - This is the main thing that digital cameras are compared
by. This is simply how many dots the camera will have in the picture it takes. The pictures that I have posted were taken
at a size of 2,560 X 1,920 dots, or pixels. This means that in the picture, there are 4,915,200 pixels, or 4.9 megapixels.
A 3.1 megapixel camera takes pictures at 2,048 X 1,536. The larger the number of pixels, the better, up to a point. A poor
quality 5 megapixel camera will not be as good as a high quality 3 megapixel camera, especially if you do not print the
pictures, but simply look at them on your computer screen. A common setting for computer screens is 1,024 X 768, so even a
3 megapixel camera will have to be sized down to 1/4 of it's original size to see the entire picture. For printing, more pixels
can make a difference.
C.C.D. - Stands for Charge-Coupled Device. Fancy
name for the part in the camera that actually 'sees' the image. Beware of cameras that use a smaller C.C.D. than the picture
size. What I mean is some manufacturers will put a C.C.D. that can see 3 megapixels into a 6 megapixel camera. The camera
runs a little program that blows up or zooms in the image, and makes it look bigger. All it is really doing is wasting memory
space. You start out with a small image, and when the camera makes the image bigger, you don't get any new information, just
the camera's best guess, and that can make the picture look fuzzy or out of focus, even if it didn't start out that way.
Zoom - There are two types of zoom, Digital and Optical. The optical
is easy to understand. Using the lenses of the camera like a telescope, the camera magnifies the image. Digital zoom is a
bit different. Let's say you have a 3 megapixel camera. It's C.C.D. is seeing 2,048 X 1,536 pixels, but you set it for a 4X
digital zoom. What this does is take the center 1,024 X 768 portion of the image and blow it up to the full 2,048 X 1,024.
If you zoom in far enough with a digital zoom, you will get just the center pixel filling the entire picture, with no detail
at all. If you take a picture with no digital zoom, you can always cut portions of the picture off once it is in your computer,
and you can use this method to center the image better if you need to. Digital zoom is a waste of time.
Memory - There are several different types of memory that digital
cameras use. The most common is Compact Flash. There is also Sony memory stick, Fuji XD, SmartMedia, MultiMedia, and Secure
Digital. A few cameras also have a built in compact disc recorder or a 3 1/2 inch floppy drive, but these will go through
batteries at a very fast rate, and usually aren't that reliable.
File Type - Digital cameras store the pictures in several different
file types. The file type will determine the quality of the picture and the amount of memory the file takes up. The most common
file types are .jpg and .tif. A .tif file takes up the most memory space - a 3 megapixel picture will be about 9 1/4 meg -
but the quality of the picture is very good. A .jpg file compresses the image, and there is a loss of quality. The rate of
compression is variable, so it is possible to get many more pictures on the same size memory card. Because of it's smaller
size, the .jpg file type is used for email and on the internet quite a bit. Normally, I take pictures using the .tif format
( highest quality ) and convert them later on my computer if I want to send them. That way, if I want to print them, I will
get the best picture possible.
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