Digital Cameras & Megapixels
Digital Cameras & Megapixels
As digital cameras and ink jet printers proliferate, those of us who grew up taking 35mm film to a photo shop for processing need to look at snapshot-sharing in a new way. For those who have yet to buy a digital camera, there are vast amounts of information on Web sites like pcworld.com on how to choose the one best for you. The most I can do here is offer a few definitions and some basic tips.
Optical Zoom vs Digital Zoom
A camera's number of "megapixels" pertains mainly to how large a photo can be printed with good resolution. A 2MP camera may produce sharp 4x6 prints, but hi-res 8x10s may need at least a 4MP camera. You also need to understand the difference between optical zoom and digital zoom. 2x optical zoom means a camera's telephoto lens can enlarge a subject to twice its size, whereas using digital zoom would mean the object's size is increased by adding pixels to the photo's DPI (dots per inch) count.
Digital enlarging always degrades an image's resolution, and whether the end result is acceptable can only be determined by experimenting. Just be aware that a salesperson may try to tell you that a 3x digital zoom is the same as 3x optical zoom. It's not. In fact you can do your own digital zooming with image-editing software on your computer, and I see no advantage in buying a camera with digital zooming.
One of the main advantages of a digital camera is that we don't have to pay to have a number of photos printed (a whole roll of film) only to discover that most are not worth keeping. We can pick and choose as we go and only print the good shots.
But how does doing your own printing compare in price and quality with the way it's done with film? Well, the quality of today's inkjet printers and the inks they use can make telling the difference between the old and new methods nearly impossible.
Printers Are Cheap, but Ink Is Expensive
However, the cost of digital printing is another matter. Inkjet printer manufacturers sell their machines at very low profit margins, knowing their real profits will come from the expensive ink cartridges that need constant replacing. Yes, you can shop around for cheaper cartridges, but may find the resulting prints to be of lower quality and/or may fade faster than name-brand inks. The expensive inks are also more resistant to thumb prints and coffee stains.
Many of us who grew up on 4x6 prints tend to think this is the natural order of things and that 4x6s are what a printer should produce. Many such printers now exist, including ones that let you bypass your computer by plugging your camera or flash memory card directly into the printer. However, these printer's limit your editing options and fill each 4x6 with expensive ink.
I prefer to edit my photos in ways that minimize the amount of ink used on, say, extraneous backgrounds.