Optical & Digital Zoom? Here's the story...(What's that #8)

One of the main selling features of the many point & shoot cameras we sell is the zoom range. In giving a capsuled description of a camera, we'll refer to the megapixel count & zoom the same way a car salesman would tout a 410 horsepower Hemi(tm) engine in describing a new truck. But you'll also see that these cameras have what's called a "digital zoom", with some cameras claiming zoom ranges as high as 30x magnification in a tiny point & shoot. What exactly is digital zoom on these cameras & are they actually helpful? First, let's talk about the whole concept of using a zoom lens. In many shooting situations, you may wish to get closer to your desired subject without physically getting closer; there's many good reasons for that (you don't want to impede or crowd your subject by being thisclose or in the case of that lion in the photo safari, he may actually consider you as part of  the menu...) & by adjusting the zoom function, you can actually control how close you can compose your subject. The zoom lenses on these cameras will start their range in a wide angle of view that will allow you to use it for landscapes or tight indoor room situations. Optical zoom uses the optics (or lens elements) of the camera to bring the subject closer. The built in motor in the camera controls the lens movement. When you toggle or press your zoom switch to "W" or "T," your subject is either magnified or reduced in size. The "W" stands for "wide-angle" (or reduce) and the "T" stands for "telephoto" (or magnify). The magnification stated when we show or sell you a camera is the amount of times a subject is closer to you from the beginning to end of the zoom range. So, the 3x zoom range on the Canon SD78oIS, currently America's best selling point & shoot camera allows you to get 3x closer to your subject from beginning to end. Simple enough, right? Digital zoom, on the other hand is not a "zoom" at all. Digital zoom crops your image and magnifies the result of the cropping. That process is called interpolation & to make the cropped area bigger, digital zoom makes up, or interpolates pixels to add to the image, which will not give you as good a picture as using optical zoom alone.When you're way back in an auditorium at your child's graduation, sacrificing some image quality to capture the moment is more important than not getting the picture at all. So, there may be a time when using digital zoom is necessary. But by in large, I wouldn't use digital zoom often in these cameras, if at all. It would be better to buy a camera with enough optical zoom to cover your needs. You may also wish to apply the wisdom espoused by Ernst Haas, a famed photographer who said that "The best zoom lens is your legs." Panasonic has tried to have the best of both worlds in introducing what they call an "intelligent zoom" in their new Lumix ZS7. An 12x optical zoom camera that has replaced the very popular ZS3, Panasonic claims that the intelligent zoom technology in the new ZS7 applies a smart sharpening on the image enhancing details, lowering noise grain and allowing an extra 1.3x digital zoom (to 16x)  with a minor loss of quality. This technology has been done before by Sony with their  "Smart Zoom" on  Cybershots & this seems to be a smarter way to apply the attributes of a digital zoom without outlandish zoom ranges with seriously sub-par results. Next, we'll cover "shutter lag", and that'll be sometime next week.