This new processor and a new front-end LSI
take the same 42-megapixel sensor that’s
found on the a7R II and literally double its
continuous shooting speed—from 5 to 10 fps.
You can store up to 76 JPEG/RAW images
or 28 uncompressed RAW files during 10
fps burst shooting. The a7R III features
a backside-illuminated Exmor R CMOS
image sensor with no optical low-pass filter.
It uses a gapless on-chip lens design and
anti-reflective coating on the surface of the
sensor’s glass seal, which Sony says helps to
improve light collection for lower noise and
higher dynamic range—up to 15 stops. The
camera has a native ISO range of 100-32,000
(expandable to 50-102,400).
Like the previous models, the a7R III
has a 5-axis in-body stabilizer that’s been
tweaked to deliver up to 5. 5 stops of correction
(the highest in the world, according to Sony).
Sony changed the shutter design as well
to reduce vibrations.
The AF system is also improved. It features
399 focal-plane phase-detection AF points that
cover approximately 68 percent of the image
area in both horizontal and vertical directions.
There are now 425 contrast AF points, compared
to just 25 on the a7R II. Its new AF system cuts
in half the amount of time it takes the a7R III
to acquire focus compared to its predecessor.
Tracking is also twice as accurate, Sony says.
While Sony is unquestionably blazing
a trail with many a7R III features, it’s also
taking a page from competitors like Olympus
and Pentax with its Pixel Shift Multi mode.
In this mode, the a7R III takes four images,
shifting the sensor by one-pixel increments
to create the equivalent of a 169-megapixel
image. As of this writing, the four still images
NOTES FROM THE
TIPA TEST BENCH
PDN is a member of the
Technical Image Press
Association, which has
contracted with Image Engineering for
camera testing. For the full lab report,
please see: bit.ly/2DDRHU4
The a7R Mark III produces images with
excellent resolution. At ISO 100, the Mark III
captures 2594 line pairs per picture height,
representing 98 percent of the theoretical
maximum. This is slightly better than the
Sony a7R Mark II, which captured 2448
line pairs per picture height at ISO 100 (92
percent of the theoretical maximum).
As the ISO increases, the resolution in
images produced by the a7R Mark III remains
good. For example, laboratory measurements
found 2393 line pairs per picture height (LP/
PH) at ISO 3200 (90 percent of theoretical
maximum) and 2251 line pairs per picture
height at the highest native ISO (ISO 25600;
85 percent of the theoretical maximum). This
consistency is improved compared to the
Mark II, which showed a greater degradation
in resolution as ISO increased.
Texture reproduction is fairly good. However,
texture smoothing is obvious at higher ISOs.
Tests of the a7R Mark III show a high
proportion of artifacts in images of low-contrast
scenes captured at the higher ISOs (ISO 6400
and ISO 12,800). Images of higher contrast
scenes at the same ISOs contain fewer artifacts.
Sharpening produced by the Sony a7R Mark
III is moderate, with overshoots along high
contrast edges ranging from 4.0 percent at ISO
100 ( 3. 9 at ISOs of 400 to 1600) to 5. 1 percent
at ISO 3200. Undershoots along high contrast
edges range from 5.0 percent at ISO 25,600, to
a maximum of 11. 6 percent at ISO 3200.
These results are milder than the strong
sharpening in the Sony a7R Mark II. The Mark
III produces slightly milder sharpening of low-
contrast edges in images shot at higher ISOs.
Visual noise results in the Sony a7R Mark III
are very good, similar to the Mark II. Noise is
just observable in images shot at the lowest ISOs,
even when modelled as if they were viewed at 100
percent (Viewing Condition 1). At higher ISOs
in Viewing Condition 1, the noise is increasingly
obvious, although less than in images produced
by the Mark II. For example, at ISO 6400, the
Mark III noise scores are 1. 9, which is better
than the 2. 2 produced by the Mark II.
In Viewing Condition 2, simulating a
postcard-sized print or the image viewed on a
mobile screen, noise would only be noticeable
at the highest native ISO, ISO 25600. This is a
slightly better than the Mark II.
GEAR & TECHNIQUES PRODUCT REVIEWS
ABOVE: The a7R III
sets a new benchmark for
mirrorless camera performance.
Hands-on with Sony’s a7R III, Photolemur and Venus Optic’s
Laowa 15mm f/2. BY GREG SCOBLETE
SONY A;R III
In our January issue, we explored the
concept of “computational photography”:
the use of processing power and algorithms
to enhance images. Computational
photography is usually mentioned in the
context of smartphones, which must lean
on algorithms in lieu of larger lenses and
sensors to coax “DSLR quality” images
from their more limited hardware. But
the bounties of our algorithmic age aren’t
restricted to mobile phones. Digital
cameras can also get in on the fun.
Which brings us to the Sony a7R III.
Take a superficial glance and you’d wonder
how Sony had the audacity to slap a “III”
on the end of it. It has the same image
sensor as the II and (mostly) the same
body design. But under the hood, the
processing engine has been completely
revamped, and in that, the magic happens.