How to use Wide Angle Lenses
Wide angle lenses refer to lenses with
shorter than normal focal length and have the effect of increasing the
angle of view rather than decreasing it. At the same time, wide angle
lenses also can decrease the image magnification at the same camera to
subject distance. There are several basic reasons for using lenses of
short focal length. Not all of these are concerned primarily with the
idea of increased angle of view, but all use it.
Wider Angle of View
A lens of normal focal length has an
angle of view ranging from 45 to 55 degrees, give or take a little.
But, from a given camera position, not all subjects will fit into this
acceptance angle. Examples of subjects that are likely to require wider
angles are landscape views and architectural studies. They are also
useful in circumstances that force you to position your camera
unusually close to the subject. Wide angle lenses are often used in
landscape photography because when people look at such views they
normally sweep their eyes across it to take it all in; the view as
photographed with a normal lens tends to look cramped. In architectural
photography the perspective effects induced by a close approach tend to
make the picture look more dramatic, even if not actually needed.
Because wide angle lenses have a greater
angle of view than normal lenses, they produce less image magnification
than such lenses when both are used at the same distance from the
subject. Thus, wide angle lenses are useful when you desire to make it
appear that a given camera to subject distance is greater than it
Another such use occurs when you wish to
exaggerate the relative sizes of subjects at different camera to
subject: distances (the opposite compared to the one produced by
telephotography). This technique can be used to place visual emphasis
on the nearer subject, when there is no need for direct size
comparisons. It is quite an effective technique.
Just as all serious photographers should
take a medium capability telephoto lens along on each session, so
should they take a moderate wide angle lens. It is not extreme demands
that cause us trouble in most circumstances, but rather those demands
that just slightly exceed the capacities of our equipment. The most
useful wide angle lens seems to be one with about 70% of the normal
focal length. In the 35 mm format or the full frame formal of DSLR,
this would be a 35 mm focal length (70% of 50 mm focal length).