After you have selected an interesting
subject in an appropriate setting, your next decision will probably
involve image size. Do you want your subject to fill the frame and
dominate the picture, or do you want it presented as merely a part of
its surroundings? If your subject is a person and you are taking a
portrait, do you require just a head and a shoulder close up or is a
full length stance more to your liking? If the subject is a landscape
spread out before you, will you favor a sweeping panorama or a medium
distance shot of an intriguing detail? It is all about controlling
magnification in camera photography.
These choices are all open to you, but getting just the effect you
desire involves three interacting factors: the actual physical size of
your subject, how far you are from it and the focal length of the lens
you are using.
It is obvious that from the same distance and with the same lens, a
horse for example, will appear bigger in your viewfinder than a kitten.
When a horse fills the frame, a kitten will still be only a small part
of the total scene. In these circumstances you can have a close up of a
horse and a long shot of a kitten based entirely on their relative
sizes. Considering just the horse alone, you can achieve either a close
up or a long shot (with any one lens) simply by walking toward it or
backing away. Camera to subject distance is the handiest control for
regulating image size.
If a subject is photographed at a fixed distance, however, the only way
to change its image size is to change focal length of camera lens. This ability
of focal length to determine photography magnification is the very reason why there
are lenses of various sizes and interchangeable lens cameras to accept
them. Suppose the horse is still standing a few feet away. If you look
at the horse through the finder of a camera equipped with a normal
focal length lens (50mm lens on a 35mm camera), it will appear large in
the frame, perhaps filling it. If you use a shorter lens, such as a
28mm, there will be much more space surrounding the horse. If you use
an extremely short (super wide angle) lens, 19mm or so, the horse will
be but a small part of the total scene. As focal length gets shorter,
the area included increases, but the image size of objects and details
Suppose you start with the subject far out in a pasture. A normal lens
will now present you with a long shot - a small horse in a large field.
If you keep changing lenses, going to a longer focal length each time,
the image of the horse will get bigger and bigger until it finally
fills the frame and everything else is excluded. As focal length
increases, so does image size.
Zoom lenses are convenient for changing image size quickly and easily.
Some have enough range to let you move in from a full figure to a head
and shoulders portrait without changing the position of you or your
Most inexperienced photographers take pictures from too far away.
Professionals seldom waste picture area. They fill it completely with
important subject matter. You can easily do the same thing by
controlling image size. Adjust your camera to subject distance or
change the focal length of your lens until you have eliminated all