Amateur Photographer - UK (2021-01-16)

http://www.amateurphotographer.co.uk 75

Those with steady hands can

expect to shoot sharp handheld

shots as slow as 1/15sec at

400mm Sony A7 III, Sigma 100-400mm F5-6.3

DG DN OS Contemporary @ 300mm, 1/15sec at

f/6.3, ISO 100

SIGMA has a knack of identifying

gaps in the market and releasing

lenses where there’s a shortage.

Before the release of this zoom

there weren’t many full-frame

lenses to choose covering the

100-400mm focal length in

E mount or L mount so it’s always

welcome to see a manufacturer

like Sigma step up and deliver an

exceptional example.

Although it does force you to

push the sensitivity higher than

you would on a telezoom with a

faster variable maximum aperture

of f/4.5-5.6, you get a reasonably

compact lens that doesn’t upset

the balance of a full-frame

mirrorless camera or feel too

heavy. It backs up its excellent

portability with superb contrast

and sharpness that exceeded my

expectations and then some.

There’s its optical stabilisation to

factor in too, that when combined

with a mirrorless camera with

5-axis in-body image stabilisation

lets you shoot sharp handheld

shots at 400mm with shutter

speeds as slow as 1/15sec.

The lack of teleconverter and

USB dock support for E-mount

versions will dishearten a few

Sony users, but this doesn’t take

much away from what is a

stunning telephoto lens and one

that represents extremely good

value for £899. Well done Sigma!

the zoom this way is ideal for
quick transitions in focal length,
but required slightly more effort
to extend it between 300-
400mm than at the wider end.
Though not weather-sealed,
Sigma has gone to the effort of
adding a dust-and splash-proof
seal around the mount and a
water-and oil-repellent coating to
the front element. The rubber
ring behind the focus ring can be
removed and an optional TS-111
tripod socket (£139) can be
attached. It won’t be necessary
for those who take a majority of
their images handheld, but for
those who’d like to support the
lens on a tripod or monopod it
does raise the price over £1,000.

Autofocus
All the switches operate with a
reassuring click and the auto
focus lock (AFL) button that’s
located between the focus limit
and optical stabilisation
switches is perfectly placed for
control with your thumb when
the lens is supported in your left
hand. Many of my test shots
were focused using the AFL
button, but when I experimented
with manual focus the focus ring
offered precise adjustment when
rotated slowly.
Autofocus performance is
smooth and virtually silent, with
subtle operational whirring only
noticeable when the lens was

held directly to my ear. The

speed of focusing is immediate

throughout the zoom range

under bright lighting conditions.

Signs of the lens hunting for

focus were only detected in dark

conditions and even then it

rarely failed to misjudge focus

with the Sony A7 III that I tested

it with. I was also satis ed by

how well the lens performed with

Sony’s face, eye and animal

subject detection modes.

Image quality

Photographing the same scene

across the zoom range at

different aperture settings before

inspecting my results revealed

the lens returns its sharpest

results towards the middle of its

zoom range between 150mm and

300mm. The level of sharpness

that’s resolved at full telephoto

is remarkably impressive for a

zoom so compact and I identi ed

that optimum edge-to-edge

sharpness at this focal length is

achieved at f/8. Corner

sharpness never reaches the

same level of sharpness as that

in the centre at any point in the

zoom range, however it remains

respectable. To return the

sharpest results possible, users

will ideally want to use the lens

between f/5.6 and f/11, with

diffraction taking the edge off

sharpness at f/16 up to its

minimum variable aperture of

f/22-f/29. As a side note, the

lens can be used at f/5 between

100mm and 115mm and at

f/5.6 up to 235mm. Beyond this

point the maximum aperture is

f/6.3 all the way up to 400mm.

Vignetting is exhibited when

it’s used wide open, as is

pincushion distortion through the

zoom range. The good news is

that both are a one-click  x in

the latest versions of Adobe

Camera Raw and Lightroom that

possess the correct lens pro le.

This lens pro le does a great job

of correcting these optical

shortcomings and individual

pro les are also available for

photographers who use the

L-mount version of the lens with

teleconverters.

I was impressed by the way

the lens handles  are and it

manages to uphold high contrast

when shooting directly towards

the light. Some purple and green

fringes were observed along

high-contrast edges on close

inspection, but the defringe

eyedropper tool in Camera Raw

v12.4 was used to remove

this quickly and effectively.

Price £899

Lens mount

Sony E, Leica L

Filter diameter

67mm

Lens elements 22

Lens groups 16

Aperture blades 9

Maximum

aperture f/5-6.3

Minimum

aperture f/22-29

Minimum focus

distance

112cm (Wide),

160cm (Tele)

Diameter 86mm

Length 199.2mm

Weight 1,140g

Included

accessories

LH770-04 lens

hood, padded

case, lens caps

Data file

LENS TEST Testbench

Ve r d i c t

‘The level of sharpness that’s resolved at

full telephoto is remarkably impressive ’

GOLD