Some of the strengths that accrue to dSLRs have nothing to do
with the fact that they are single lens reflex cameras.
■ Higher sensitivity and
reduced noise.
The images from most non-dSLRs begin to break down when
sensitivity is increased to ISO 400 or more, primarily because of excessive noise.
Few of these cameras have an ISO setting that’s usable.
In contrast, many dSLRs generate relatively low noise at ISO 800, and produce
acceptable images at ISO 1600, ISO 3200, and beyond. The improved quality
offered by digital SLRs is due to the larger sensors available in these
cameras. As vendors pack more and more pixels into the tiny CCD sensors found
in non-SLR cameras, the pixels become smaller and more prone to noise. The
larger pixels in the CMOS and CCD sensors of dSLRs have much less of a tendency
to produce the random grain we see as noise, and are more sensitive, to boot,
producing higher effective ISO speeds.
The larger sensors require lenses with longer focal lengths, so
the dSLR use regains the control over depth-of-field that is such an important
creative tool. Ignore those “35mm equivalent” specs you see posted for non-dSLR cameras. That “38mm” zoom setting on your
point-and-shoot digital may provide the same field-of-view as the moderate wide
angle you’ve used on your film SLR, but the
depth-of-field is more akin to what is native to the 6mm actual focal length of
that lens. You’d think the “380mm” setting would give you roughly the same narrow
depth-of-field you’d expect from a 400mm lens on your
film camera, but what you end up with is the same field of sharpness offered by
a 60mm lens. Anyone who’s used a consumer digital camera
knows that at non-macro shooting distances, virtually everything in the picture
is sharp, at any zoom setting and at any f-stop. If you plan to use
depth-of-field creatively, as in the photo shown in Figure 1.4, in which the background
was thrown out of focus to emphasize the flower, you’ll
need a dSLR with a larger sensor.
■ Digital SLRs work like a
camera, not a VCR.
I own a Nikon CoolPix 995, which was one of the best $1,000
digital cameras of its time, and still a champ among 3.3MP models for sharp
images and macro performance. Still, this camera drove me nuts. Even after I’d owned it for a year I had to take along a cheat sheet that
told me how to activate infrequently used features, such as manual focus. I used
the 995 a lot, but I still had to refer to my crib notes to see which menu I
needed to refer to to activate a particular feature, and then which buttons to
press to make it work. It was a great camera, but it didn’t
work like one. The same situation exists today with the vast majority
of nondSLR cameras. I have the opportunity to test eight or ten point-and-shoot
cameras in all price ranges each month, and virtually all of them operate more
like VCRs rather than like cameras. When you zoom in and out, do you want to
press a couple of buttons and wait while a teeny motor adjusts the lens
elements for you, or would you rather twirl a zoom ring on the lens itself and
be done with it? To switch to manual focus, wouldn’t
you prefer to flip an AF/MF button and then twist the focus ring on the lens,
instead of pressing a Menu key, finding the Focus setting, switching to Manual
focus, and then pressing a pair of left-right cursor buttons?
Photo enthusiasts won’t put up with that
nonsense when they’re trying to take pictures. The dSLR I use has separate buttons for burst mode, ISO
settings, white balance, EV adjustments, metering mode, and resolution. To adjust any of
those, I hold down the appropriate button and thumb the command dial to choose the setting
I want. Set the camera to shutter- or aperture-priority (with a dial, not a
menu) and move the command dial to adjust the f-stop or shutter speed. In manual exposure
mode, there are separate command dials for shutter speed and aperture.
That might seem like a lot of buttons to master, but, trust me,
you’ll learn to use them much more quickly than you’ll memorize
the menu system of the typical point-and-shoot.
■ Faster operation.
You’ll find that dSLRs work much faster
than point-and-shoot digital cameras. One of the metrics used to measure point-and-shoot
performance is “time to first shot.” That is, once you decide to
take a picture and switch the camera on, how long must you wait until the
camera is actually ready to shoot? Generally, you’ll
have to wait 3 to 5 seconds or more; then wait another second while the camera
autofocuses and calculates exposure after you've
pressed the shutter release. Switch a dSLR on, and it’s
ready to go. On more than one occasion I've spotted an
unexpected opportunity, switched my digital SLR on as I brought the camera to
my eye, and then took a picture, all within less than one second.
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