AI News, Cameracraft Sept/Oct 2019 by Icon Publications Ltd artificial intelligence
- On 8. november 2019
- By Read More
Sony A7R II review by David Kilpatrick
Sony’s A7R II has a unique position in the mirrorless ILC world, creating the largest image files at over 42 megapixels from an in-body five axis stabilised sensor with exceptional performance given by backside illuminated CMOS.
All three make slightly different points, and reflect growing experience of the camera which I bought from WEX as one of the first despatched on July 28th. The UK best body-only price then fell from their £2,695 to just over £2,000 from one main Sony dealer (at an event promotion) in under three months.
Despite finding bargain deals or importing directly, since the introduction of the A99 only three years ago I have lost about £3,500 keeping up with Sony full frame camera bodies.
My kit includes the 12mm mentioned above, the 16-35mm f/4 Carl Zeiss OSS, the 24-240mm f/3.5-6.3 Sony OSS, the 28mm f/2 Sony OSS FE (look out for individual reviews shortly); a 40mm Canon f/2.8 STM pancake, a 24mm Samyang tilt-shift, 85mm Sony SAM f/2.8, Sigma 70-300mm OS and a whole bunch of interesting older stuff used on adaptors.
With the Lens Correction App configured for SS with each manual lens, the very high resolution of the A7R II sensor allows a stable view for precision magnified focus well beyond the ability of any AF method or reliance on focus peaking alone.
The results show me quickly which lenses are excellent performers without needing an optical bench or test charts (give me a single LED light and a darkened room, and I can find out what I need to know about any lens very quickly).
Most Sony and Sony Carl Zeiss zooms do yield good sharp images on 42 megapixels but it’s easy to exceed their best by fitting something like my 1970-ish SMC Takumar 50mm macro (used for the shot above), or even my Russian 50mm f/2 tilt-adapted Zenitar.
I found the 28-70mm f/3.5-5.6 OSS which was fine on A7 II inadequate for critical quality on the A7R II and after tests concluded the 24-240mm was the best option to replace it. To learn why FE/E mount zooms and OSS lenses are never likely to blow away fixed focal length unstabilised types like the Zeiss Loxia or adapted classic RF and SLR optics, wait for my 24-240mm review.
As with downsizing or lens based cropping, I can crop full frame captures right down to less than a quarter of the A7R II image and have a file acceptable to Alamy for stock library use, or to a client directly for almost any reasonable editorial use.
On the A7R II, using its maximum 12mm shift reveals serious loss of outer field sharpness even at apertures like f/10, f/11 and f/13 which are optimum on other ways.
The same kind of strong cropping works for telephoto wildlife shots (300mm lens, better than 500mm on 14 megapixels) and for macro work (1:1 on full frame, 2.2:1 at 14 megapixels).
Having used two other A7 series bodies, and started the transition to the FE lens series with some mix of adapted glass on the way, why didn’t I stick with the far more realistic and practical A7 II, or the A7R which was paid for and at 36 megapixels just as useful a large file size?
Where Minolta A, Fuji X, Pentax, Leica and nearly all good makes secure the body and lens bayonet mounts using six screws, the E-mount uses only four even for the top end bodies which may have to support lenses approaching 1 kilo in weight.
The four-screw fitting creates two axes of potential tilt restrained only by diametrically opposed screws, six-screw design is better but actually a five screw design beats both as you can’t draw a diameter across any two screws and create a tilt axis.
The E/FE lens-body system is built round a concept of achieving final accuracy in alignment and focus without needing precision in every component. The nominal 18mm mount to sensor register doesn’t have to be perfect (and seems to vary by at least ±0.1mm).
I’m sure Zeiss makes due allowance in the design of manual focus Loxia lenses, and Voigtlander has specifically allowed the new E-mount range planned for 2016 (10mm, 12mm and 15mm) to focus past infinity because they are aware of the variable register of the system.
Secondly, the A7R II has such large files and a slow overworked processor relative to those files and the massive task of running a high resolution, high frequency EVF and many clever software functions. Any kind of systematic ‘chimping’
With Firmware V2.0 I’ve seen typical write to card times halved but identical shots could take varying times and the worst case remains close to 10 seconds for the light to go off on a single shot.
Most of time it’s clearing about 1 second after 2 second auto review, and disabling auto review has no apparent effect on this, or the time the camera takes to respond to a fresh shutter actuation.
As a rule, if you can lock the camera down (tripod) or use a very fast exposure (studio flash, shutter speed 4X the focal length of the lens) shooting with no stabilisation at all will offer the best results.
16mm landscape with careful focus checking, and only just enough depth of field even at f/16 if the end result is going to be a 1m wide print Read the manual, think about all the functions of the camera, assign your custom buttons, set your parameters.
My set-up includes (routinely) Auto ISO 200-1600 because within that range the A7R II files have low noise and good textural sharpness and there’s no great benefit in dropping to 100;