Cracking the code on digital cameras

By: DON EDRINGTON - For the North County Times | Sunday, April 16, 2006 9:18 PM PDT ∞

If you're new to digital cameras, some of the terminology can be pretty confusing. However, if you type "digital photography" into a search engine, countless articles can be found that give very comprehensive explanations.

In the meantime, here are some basics that should help simplify things.

Digital images are made of tiny dots called pixels (picture elements). On paper, 300 DPI (dots per inch) is adequate for printing the average snapshot. Photography prepared for glossy magazines requires 600 DPI and higher. The higher the number, the more an image appears to have "continuous tone" color gradients.

An image seen on your PC monitor, however, will only display about 72 to 96 DPI. Since most photo-editing programs let you choose the DPI you prefer, less than 100 is fine for screen views, while 300+ should be used for prints. Check your printer manual to learn its DPI options.

Speaking of "screen" view, it's important to understand that the size you see on your monitor and the actual print size may be two different things.

Screen views can be enlarged if you want to edit an image, say, one pixel at a time, or reduced if you want to place multiple pictures on a single page.

Another reason for reducing the screen view of an image is that many cameras produce such large photos that they often need to be reduced to about 25 percent just to fit on your monitor. This happens to be a weak point of Windows Paint, which will let you enlarge a picture's screen view to 800 percent, but it has no setting below 100 percent. My favorite editor for enlarging or reducing both the screen and actual print views is Irfanview.

Picture dimensions are normally measured in pixels, however most photo-editors let you set measurements in centimeters or inches, as well.

These choices are often found under "Image" and under "File>Print."

Another number that can be confusing is how many "megapixels" a camera is capable of. Simply put, a larger MP number means a print will have higher pixel resolution and prints can be very large. I have a 6 MP Canon, but most of my work could be handled just as well with a 3 MP camera.

Another important number refers to zoom capabilities. "6x optical zoom" means your camera's lens is capable of enlarging an image to six times its normal size. However, "2x digital zoom" means an image can be doubled by software that "guesses" at the colors of pixels needed to fill in the enlargement. If zooming is important, go by the "optical" number rather than the "digital" number.

Again, look these things up online for more complete explanations. Sites such as www.pcworld.com and www.cnet.com not only give price comparisons of cameras and accessories, they print user reviews of most items ---- both good and bad.

As for image-editing programs, there are dozens and they can be confusing to use. However, they all come with extensive "Help" options.

More tips can be found at www.pcdon.com and calls are welcome at (949) 646-8615.