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The lens handles tricky backlit scenes
exceptionally well with no sign of flare
or chromatic aberration in this example
Sony A7R IV, Sigma 14-24mm F2.8 DG DN Art at
24mm, 1/1000sec at f/11, ISO 800
Haysden Park Sony A7R IV, Sigma 14-24mm F2.8 DG DN Art at 14mm, 1/125sec at f/5.6, ISO 400
weight saving to be made
too. Unlike its wideangle
sibling that weighs over a kilogram,
this lens is 355g lighter at 795g.
The weight saving is actually
rather surprising given it has more
elements in a greater number of
groups. Whereas the Sigma
14-24mm F2.8 DG HSM is made
up of 17 elements in 11 groups,
this lens features a construction of
18 elements in 13 groups.
Included within this construction
are fi ve special low-dispersion
(SLD) glass elements and one ‘F’
low-dispersion (FLD) glass
element. This low-dispersion glass
is used to curtail chromatic
aberration, which is known for
being problematic in large-
aperture ultra-wideangle lenses,
especially towards the edge of the
frame. To prevent fl are and
ghosting when shooting towards
the light, Sigma has combined its
Super Multi-Layer Coatings with abut a glance at the rear reveals it’s
equipped with a rear fi lter holder
and robust metal mount.
Elsewhere it supports full-time
manual focusing and has a
minimum focus distance of 28cm.
The lens is supplied with three
accessories in the box – a padded
case, rear cap and a push-on front
cap that has felt lining on the
inside to create a tight, secure fi t.Premium build quality
Sigma lenses that are embellished
with the letter ‘A’ in a silver circle
on the barrel have gained an
excellent reputation for having a
first-class fi nish and robust build
quality. The same is true of this
lens. Though it may be
considerably cheaper than main
brand rivals, this doesn’t show in
the quality of its build. The
construction of the barrel is a
blend of precision-engineered
metal and smooth matte black
polycarbonate plastic, with
rubberised zoom and focus rings
offering good control when your
hands might be wet or you’re
wearing gloves. The zoom ring has
ashort throw, operating very
smoothly across the zoom range
in just under a quarter turn. Thenew Nano Porous Coating. The
idea behind this is that the porous
silica layer has nano-sized holes
with air inside. Having holes of this
size enables a large reduction in
the refractive index, allowing the
refl ectance to be lowered more
than conventional anti-refl ective
coatings. As a result, Sigma claims
any refl ected light that can cause
fl are and ghosting is greatly
reduced, thus achieving sharp and
high-contrast images even in
backlight conditions.
Complementing the complex
construction is a 11-blade
rounded aperture diaphragm,
which can be set between a
maximum aperture of f/2.8 and a
minimum aperture of f/22. As for
autofocus, the lens relies on a
stepping motor to keep the AF
drive fast and silent. You also get a
focus lock button on the barrel
below the AF/MF switch that can
be set up from the camera’s menu
to perform different functions.
The bulbous front element does
extend slightly when the zoom is
being retracted from 24mm to
14mm, but the fi xed petal-shaped
hood does a good job of shielding
it. I’ll touch on how the lens is used
with fi lters in more detail shortly,