lenses and close-up equipment. With many other camera types your
choice of accessories is far more limited or nonexistent.
A rangefinder camera has a single lens like an SLR, but you don’t view and focus
through it. Instead, you compose your picture by looking through a viewfinder
usually located above the lens and to the right (as you look at the front of the
camera), and then focus using a rangefinder, a measuring device that links the
viewfinder and lens.
The rangefinder works with a prism behind a window located on the opposite
side of the lens from the viewfinder (on the top left as you look at the front
of the camera). As you turn your lens to focus the subject, the prism rotates and
bounces light sideways to a mirror in the viewfinder. This produces a double
image of the subject—one from the viewfinder and one from the prism. The
double image appears as a translucent rectangular or square patch floating in
the middle of the viewfinder. The image from the prism moves as you focus the
lens; when the two images superimpose, the subject is in exact focus.
One advantage of rangefinder focusing is that the viewfinder is bright and
always visible. With SLRs, when the reflex mirror flips up to expose the film,
the viewfinder blacks out briefly. Rangefinder cameras have no reflex mirrors,
which allows you to maintain sight of your subject at all times.
The lack of a mirror also makes a rangefinder quiet and easy to hold steady
when using slow shutter speeds. You may even be able to handhold your camera
at shutter speeds as slow as 1/8 of a second, or even 1/4 under some circumstances,
and still get sharp results, unlike SLRs which cannot usually be safely
handheld at shutter speeds slower than 1/60 or 1/30. The lack of mirror and
pentaprism also makes a rangefinder camera compact. This is good for 35mm
models, but especially advantageous with medium format; medium-format
rangefinder cameras can be handheld more easily and at slower shutter speeds
than most medium-format SLRs.
The biggest disadvantage of rangefinder cameras is that they don’t permit
through-the-lens viewing. Viewing the subject through a separate viewfinder,
rather than through a lens, means that you may need a different viewfinder for
every lens you use. Good rangefinder cameras do offer adjustable or accessory
viewfinders or markings in the viewfinder that show what different lenses see.
But none of these solutions is as precise as seeing directly through the lens.
Thus rangefinder cameras do not offer as many different types of lenses and
other accessories as SLRs.
The lack of through-the-lens viewing also may lead to parallax error, the difference
between what you see through the viewfinder and what the lens sees (and
the film records). This is because the viewfinder is usually a little higher and to
the left of where the lens points. When your subject is far away, parallax error
is usually not a factor; what you see through the viewfinder is pretty much what
you will get on film. But parallax error becomes increasingly evident the closer
you get to your subject. Some viewfinders adjust for parallax error automatically
or include parallax-compensation lines that guide you as you adjust your composition
manually. In general, to compensate for parallax error, you have to
aim the rangefinder up a little and to the left.
A view camera is like a camera from the early days of photography. Using
one takes practice, but its design is simple enough. It has a lens mounted on a
front standard to capture the scene and a slot on a rear standard to hold the
film. Between the front and rear standards is a collapsible bellows, a light-tight
accordion-like tube made of cloth, leather, or some other material. A view
camera takes large-format sheets of film or a high-quality digital back, making
it capable of producing finely detailed, sharp photographs.
The view camera lens is mounted on a lens board, and in the rear there is a
focusing screen called a ground glass. A film holder, a removable accessory that
contains the film or digital back, is inserted between the bellows and the ground
glass. The bellows sits on a rail (or a platform); you turn a knob on the front or
back of the camera and the bellows collapses or expands to achieve focus.
You view and focus the subject on the ground glass, which is positioned
behind the lens and bellows; the image forms upside down and laterally
reversed. Ambient light makes the image hard to see, so you must cover your
head and the ground glass with a dark focusing cloth to keep extraneous light
out. When your subject is in focus, you slip a film holder or digital back between
the ground glass and the bellows, or replace the ground glass with a digital
back, remove the dark slide that covers the film on one side of the holder,
and take your picture.
A view camera offers more control over the image than any other camera
type. The front and rear standards move independently and tilt and swing in a
variety of directions, which gives you very precise control over focus, as well as
the ability to correct or distort perspective, such as straightening converging
lines when you’re pointing the camera up at a tall building. The view camera
also accepts a wide array of accessories, lenses, and film formats.
On the other hand, a view camera is large and cumbersome, and must be used
on a tripod. It is not practical for making candid and spontaneous pictures.
It also may be expensive, though view cameras are available for a wide range
of prices.
A popular variation of the view camera is the field camera, which is a good
choice for landscape photography because it is light and folds into a neat package
for easy portability. It delivers many of the benefits of the view camera, including
high image quality. A field camera is not as versatile as a view camera,
however; it doesn’t take as many accessories and has fewer front and rear
controls for adjusting focus or perspective
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