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Chapter 7 Close-up Photography and Photomacrography
Close-up lenses are positive supplementary
lenses that shorten the focal length. A supple-
mentary lens is an extra or add-on lens. See
Chapter 3 for the defi nition of a positive lens.
They are available in different powers. Each
is good for a different limited range of close-
up distances.
The lenses usually come in a set of three,
+1, +2, and +4. See Figure 7-9. The higher the
number, the greater the magnifying power.
They may be stacked to increase magnifi ca-
tion. A +1 lens and a +2 lens equals a magnifi -
cation power of a +3 lens. You should always
attach the highest number to the lens fi rst.
Stacking reduces sharpness.
Close-up lenses are easy to attach. Like
fi lters, they are threaded to fi t the front of the
regular lens. See Figure 7-10. Close-up lenses
are simple, convenient, inexpensive, and do
not require exposure compensation.
Reversing Ring
A reversing ring, Figure 7-11, is an adapter
that permits the lens to be reversed on a cam-
era. It is the least expensive way to practice
photomacrography. The reversed lens will
give a magnifi cation ratio of 1:1 or life-size
with a 50 mm or “normal lens.” However, the
automatic features of the lens are lost.
Lens Extension Tubes
Closer focusing of a lens is possible by
using an extension tube, a device for moving
the lens farther from the fi lm plane. Exten-
sion tubes, Figure 7-12, are used to extend
the lens. This technique has limitations. As
the lens extension length grows, the expo-
sure time increases and image sharpness
decreases.
Figure 7-9. Close-up lenses are positive
supplementary lenses that shorten the focal length of
the regular lens.
Figure 7-10. Close-up lenses are threaded to attach
to the front of the regular lens.
The way a lens is normally
mounted to camera body
Reversal
ring
Part of lens that is
normally locked to
camera body
Figure 7-11. A reversing ring is an adapter that
permits the lens to be reversed on the camera for
very close focusing.