In order to isolate the main subject from any distracting surrounding
elements one should use a large (open) aperture, getting a shallow
depth of focus. This creates the effect that objects before and behind
the main subject are blurred, isolating the main subject.
In this picture of the first stage in Edmund Davidson's WIP
of making a Full Integral, I decided to show the "raw" bar of steel
with the plexiglass template but also moved the edge of the
magnifying glass into the focused zone for "design" purposes.
Bringing the magnifier into the picture added nice color in contrast
to the edge of an out-of-focus cabinet, giving it a touch of contrasting
cool & warm shades.
It is always worth the few seconds of beforehand planning - like
moving the camera position and angle of view, or clearing unwanted
"stuff" out of the way, until a satisfying result is achieved.
One should watch out in particular for out of focus background objects
that may appear as blurred elements sticking out of the main subject...
All the best,
David Darom (ddd)
In this picture I cropped most of the blurred foreground
as I later preferred to get closer to the subject for a full page illustration.