deep DOF while in general a lens focused close-up has a more
shallow DOF.
And we don’t always want everything in focus. In fact, aside from
“sharpness,” the other term often discussed by photographers is
“bokeh,” which refers to the lovely out-of-focus areas behind your
subject. Lenses have a good or poor “bokeh” and the relative bokeh
of various lenses is fiercely contested. Bokeh is like the difference
between the harsh camera shots of a newscast and the soft
feathery feel of many movies, where the subject is in focus against
a wash of blurry and lovely pastels.
In taking a photo, we first select a focus point; we focus. Then, and
only then, we decide on how much depth of field we need by
adjusting the aperture. Of course, due to various light and other
conditions we don’t always have much choice in the real world. But
theoretically we do.
If we go wide-angle, we have more depth of field and if we go
telephoto we have a more narrow depth of field. That is why with
wide-angle lenses there is often little to no bokeh because
everything is too much in focus. And with telephoto lenses we can
have the subject in exact focus against a nice blurry background –
good bokeh.
When we are close up, we tend to have a very narrow DOF, while
shooting at a distance with a narrow aperture gives us a wider
depth of field -- more of the subject is in focus.
And while this topic is too complex to go into here in detail, there
are three factors that help to determine your depth of field:
aperture, focal length of the lens, and distance to subject.
Narrow DOF Greater DOF
We can get greater DOF by using a small aperture, a wide angle
lens, and by standing far back. However these three factors don’t
all work together smoothly for close-up work. If we stand far back
with a wide-angle lens set to a small aperture we get a great depth
of field of whatever is at infinity but it won’t help us in macro and
close-up photography.
For close-up work we have to mix and match techniques to get any
kind of depth of field and the history of photography is filled with