Those of you with point-and-shoot cameras thought you got off easy on this one, didn’t you? Just because your lenses are permanently attached doesn’t mean there aren’t a few things worth knowing. Focal length, zoom, and the ever-troublesome digital zoom are all important factors to know and understand when comparing one point-and-shoot camera to another.
Focal Length and Zoom
Just as on the interchangeable lenses made for dSLRs, the focal length on your built-in lens is measured in millimeters, but the scale is dramatically different. The built-in lens likely has a focal range with smaller numbers than you would expect to find on dSLR lenses. For example, the focal length of the lens on one of my point-and-shoot cameras is 6–22.5mm (which works out to a dSLR equivalent focal range of something like 28–105mm). Because of the difference in scale, you can’t compare the numbers at face value, but the principles still apply. Smaller numbers mean wider focal lengths, and larger numbers mean more telephoto focal lengths.
What you’re really looking for when it comes to the built-in lens on a point and shoot is the range between the two numbers. The larger the range, the more pronounced your zooming capabilities are. The shorthand way of communicating this is by assigning your camera an “x” zoom number.
If the lens can zoom from 5–25mm, it’s said to have 5x zoom. Or, as in my point and shoot’s case, 6–22.5mm is the equivalent of a 3x zoom. The higher the x value, the greater the zoom range.
Digital Zoom—just Say No!
TV crime dramas would lead us to believe that digital zoom is the cat’s meow. Even my beloved “Law & Order SVU” makes me giggle when super-zoomed, pixelated security camera footage shot from 300 yards away (in the dark) is analyzed, cropped even closer, then suddenly—as if truly touched by magic—becomes crystal clear, revealing an identifiable birthmark behind the criminal’s left ear (cue the music).
Manufacturers have been known to make desperate attempts to seduce you with seemingly impressive features like “digital zoom.” Nothing more than glorified in-camera cropping, it’s actually one of the worst things you can do to your photos (as you’ll see in Chapter 6).
Also measured with an x number (3x, 5x, or more), digital zoom picks up where optical zoom (what your lens is inherently capable of) leaves off, allowing you to zoom further than nature intended. To give you an example, I captured Figure 4.11 by zooming the lens as far as optical zoom would let me go.
FIGURE 4.11 These Colorado mountains were captured at the furthest extent of my point and shoot’s optical zoom capabilities.
Figure 4.12 shows how much closer digital zoom allowed me to get. A pretty dramatic difference, isn’t it? The trouble is it’s actually quite misleading.
FIGURE 4.12 This shows the same scene captured by maxing out my digital zoom. That’s a pretty ginormous difference, wouldn’t you say? As you’ll see in Chapter 6, it’s not healthy for your photos to be enlarged this way.
If you look at the metadata (digital photo guts) for this image, you can see proof that both images were actually captured at the same focal length. Digital zoom only makes it look like Figure 4.12 was photographed at a greater focal length. In reality, it’s just a digital enlargement of the optical image captured by the sensor. Unfortunately, the quality is not the same as if the image had been captured optically, instead of with digital zoom.
Thankfully, many point-and-shoot cameras have the option to turn off digital zoom to avoid accidentally employing it. If your camera is one of these, I highly recommend it as digital zoom can be a serious-quality buzz-kill (especially if you continue the bad habit of further cropping your photos in post-production).