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› Macro lenses
› Teleconverters
For specialist close-up work there is little
to beat a true macro lens. For more on
these see page 165.
Teleconverters are supplementary optics
which fit between the main lens and the
camera body, and magnify the focal length
of the main lens. Nikon currently offers the
TC-14E II (1.4x magnification), TC-17E II
(1.7x), and TC-20E II (2x). The advantages
are obvious, allowing you to extend the
focal length range with minimal additional
weight (the TC-14E II, for example, weighs
just 7oz or 200 grams).
However, teleconverters can degrade
image quality—as you might expect, the
higher the magnification factor of the
converter the more noticeable this is.
The TC-20E III, in particular, produces a
significant loss of sharpness, especially if
you try and shoot at maximum aperture.
Results improve when the lens is stopped
down to f/8 or f/11—beyond this,
sharpness tails off again due to diffraction.
Converters also cause a loss of light.
Fitting a 2x converter to an f/4 lens turns it
into an effective f/8. One consequence is
that the camera’s autofocus may become
sluggish or will only work with the central
focus points.
AF-S TELECONVERTER TC-20E III
COAST CLOSE-UP
A 2x converter doubles the focal length of your
lens with minimum weight penalty. 110mm,
1/1600 sec., f/7.1, ISO 800.
› Lens hoods
A lens hood serves two main functions: it
shields the lens against knocks, rain, and
other hazards; and excludes any stray light
which does not contribute to the image
but may degrade it by causing flare. Most
Nikkor lenses come with a lens hood.
201
THE EXPANDED GUIDE
LENSES
»
LENS TYPES
Nikon D5300 Ch7 184-207 P2 RY.indd 201Nikon D5300 Ch7 184-207 P2 RY.indd 201 19/02/2014 17:1019/02/2014 17:10
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