Wayne Adult Community Center
Feature article from the September, 2004 Newsletter

 

Thinking of Buying a Digital Camera?

Digital cameras are fast displacing film cameras because of the immediacy, convenience and economy that digital photography offers.  Although digital images still fall short of the best film images, they are quite adequate for everyone except demanding professionals.  In fact, to most of us there is no discernable difference.  However, not all digital images are equal, and the major factors that determine their quality are in the camera you use.

 The two features most touted in ads for cameras are the number of pixels and the amount of zoom.

Pixels (short for “picture elements”) are the individual tiny pieces that make up a digital image.  The more pixels a camera has, the higher the potential resolution (i.e. sharpness) of the images it produces.  And in turn, the higher the resolution, the bigger you can make the final print without it looking indistinct.  Consumer-grade cameras (as distinguished from professional grade) typically have at least 3 megapixels these days.  That’s enough to support enlargements of 8”x10” and sometimes even more.  In fact, if you are sure you’ll never want anything bigger than a 4”x6” print, or that you will only use the images in Email, then even 2 megapixels could be adequate.

“Zoom” is the range of magnification available to you.  A zoom range of, for instance, 3:1 means that if you set the lens at the maximum point of the range, the scene is brought 3 times closer than at the minimum point.  We’ll have more to say about zoom below.

The camera lens

                    A poor lens will blur a picture no matter how many pixels the camera has.  You’re more likely to get a good lens in a camera from a well-established firm such as Canon, Nikon, Kodak, Minolta and a few others.

                     Most digital cameras have zoom lenses.  There are three zoom numbers that may be quoted in any given ad:  Optical zoom, digital zoom, and total zoom.

 IGNORE “digital zoom”:  So-called digital zoom is achieved by internal cropping of the picture.  That is, the camera uses only a part of its sensor and then transmits that partial image as the whole picture.  The result looks magnified, but it’s just the result of spreading fewer pixels over the same area.  It’s not real.

 “Total zoom” includes both optical zoom and digital zoom, so ignore total zoom also.

Optical zoom is the only figure that represents the real zoom capability of the camera.

Illustration of camera specifications 

  Supporting software

 Un                         Unless you take the camera’s memory card (its reusable “film”) to a photo kiosk or other photoprocessing outlet, you will be downloading the images to your computer, which is to say that you’ll be copying the images to the hard drive.  The downloading is done via software that comes with the camera.  The camera will probably also come with software that will enable you to make adjustments to the picture.  It might let you determine how much to compress (that is, “squeeze”) the image file in order to save storage space and speed transmission through the Email.  Good software will have the capability of adjusting things including brightness, contrast, vividness of the color, and possibly other characteristics, as well as to remove the “red eye” so often seen in flash pictures.

 If you’re serious about working on the images, you can buy image-manipulating software separately, that will have additional capabilities.  For instance, it could enable you to remove blemishes from people’s skin.

 If you print your own pictures, using your computer’s printer

The quality of the printer is important.  Although you don’t need a printer designed specifically for photos, you do want one with good printing resolution.  Look for at least 2400x1200 dpi (dots per inch).

   The paper is also important.  You can make passable prints on ordinary paper, but photographic paper will give results like those you would get from a photoprocessing laboratory.  Choose glossy paper.

   If you want to keep the prints for a long time, pay attention to the ink cartridge you use in the printer:  Cheap inks dry slowly and fade relatively quickly over time.

There are other factors influencing image quality, but the ones mentioned above are the most significant ones for everyday photography.

 In addition to the features discussed above, there may be others that appeal to you, such as the size of the on-camera display or the ability to take several pictures in rapid succession.  Those are matters for a much more detailed article, such as the review in the May, 2004 issue of Consumer Reports.

 Two last bits of advice:

 (1) When looking at (and trying out) cameras in the store, don’t judge picture quality by the little display on the back of the camera:  Images that look fine at a size of 1.8” can look terrible at 4x6.

 (2) Realize that as the technology continues to advance, progressively better digital cameras will become available and prices will continue to drop.  Today’s top-of-the-line camera is tomorrow’s entry level model.  That is the way of all digital technology, so don’t feel bad when you buy a digital camera only to see several months later that a more advanced model has appeared, possibly even at a lower price.  If you were to buy that one, you would have the same disappointment six months or a year after that.  So buy one when you’re ready to go digital, and enjoy it.

 

W. A. Shapiro



11/5/04-2125