SONY A7R IV
SONY A7R IV If you didn’t think Sony was really serious about competing in the pro camera market, here’s the proof – the most resolution you can buy this side of ten grand. And in the compact A7 series form factor too.
With its new mirrorless camera and lens program in top gear, Sony has got its eyes on the top spot in the interchangeable lens camera market. With 61.2 megapixels of resolution on tap and some exceptional performance capabilities, including more AF upgrades, the A7R IV is certainly going to help it get there.
Undoubtedly the most successful of the digital-era arrivals looking for a slice of the still camera market, Sony has not only been a serious challenger to the traditional photo brands, but looks all set to take the number one spot in interchangeable lens cameras. Canon sincerely hopes the EOS R5 and R6 will help keep the rampant Sony at bay.
Sony got off to a solid start by taking over the Konica Minolta camera business and from this sprang its first generation of DSLRs. But pretty quickly afterwards it starting doing things its own way and has never looked back. At the heart of Sony’s success is the A7 series of full-frame mirrorless cameras and the ever-expanding FE lens mount system that currently numbers 35 models, spanning 12mm to 600mm.
The rapid expansion of the lens system has undoubtedly help convince buyers that Sony was in this for the long haul, as has the steady evolution of the A7 line – now in the fourth generation since it was launched back in October 2013. With 61.2MP of resolution on tap, the A7R IV makes a bold statement about Sony’s intentions… catch me if you can.
Compared to the A7R III – which has a resolution of 42.4MP – the A7R
IV’s sensor represents an increase in resolution of nearly 45%, which is quite substantial and will, all other things considered, make a difference in terms of image quality. And as we are talking Sony here – the company has nailed image sensor design more comprehensively than any other (you’d be surprised how many cameras have a Sony-made sensor under the bonnet). It also knows a thing or two about processing raw data off the sensor and, in particular, creating highly effective noise-reduction algorithms.
Pumping Pixels
Not surprisingly, the sensor is a backside-illuminated (BSI) CMOS in Sony’s Exmor R series to make the most of the available space on the front surface. It has an imaging area of 23.8mm x35.7mm with a total pixel count of 62.5 million, and there’s no optical low-pass filter because you want every bit of definition that’s on offer here.
The sensor is paired with Sony’s current-generation Bionx X processor and an additional front-end LSI – a configuration already seen on other recent A series models – which delivers 16-bit image data processing, output as a 14-bit RGB RAW file. Consequently, you can have 14-bit uncompressed RAW files, 12-bit compressed RAWs and, of course, 8-bit JPEGs. Tellingly, Sony claims a dynamic range of 15 stops – pretty impressive given this is directly linked to the sensor’s signal-to-noise ratio and, in turn, pixel size. The effective pixel count of 61.2 million produces a maximum image size of 9504x6336 pixels at the 3:2 aspect ratio. For JPEG capture, there’s a choice of three image sizes, three compression levels and four aspect ratios – 3:2, 4:3, 16:9 and 1:1.
The latter three are all crops, but you’re obviously still looking at very high resolutions – 54, 51 and 40 megapixels respectively. The new sensor’s sensitivity range is equivalent to ISO 100 to 32,000 with extensions down to ISO 50 and up to ISO 102,400.
The Bionz X processor is a powerhouse so, even at full resolution, you can still shoot continuously at up to 10fps with AF/AE adjustment between frames. Drop to 8fps and you can have real-time EVF framing as well (i.e. no blackout or freezing). There’s a bigger buffer memory so the burst length for
best-quality JPEGs is around 68 frames, and it’s the same for compressed RAW. With uncompressed RAWs, the buffer is good for around 30 frames. The A7R IV has dual memory card slots, now exclusive to the SD format with UHS-II speed support.
With all that resolution to play with, when the camera switches to the APS-C format with E mount lenses, the maximum image size is still a healthy 6240x4160 pixels (25.9MP) and, for
JPEG capture, you also get a choice of three image sizes, three compression levels and four aspect ratios. The buffer lengths roughly triple.
As before, image stabilisation is provided via sensor shifting with five axes of movement and correction for camera shake of up to 5.5 stops, depending on the lens focal length in use. Sony takes sensor shifting further to deliver an ultra-high resolution multi-shot capture mode. You really want more resolution? Well, with the Sony’s Pixel Shift Multi Shooting modes – there’s either four-shot or 16-shot options – you can have a monster 240.8MP file sized at 19,008x12,672 pixels. The four-shot mode performs a one-pixel shift left, right, up and down so full RGGB colour is captured at each pixel point, enhancing both detailing and colour reproduction. The 16-shot mode uses both full- and half-pixel shifts to increase the resolution as well. In the field, the camera needs to be on a tripod to use the high-res modes – and a sturdy one at that – and the subject needs to be static, such as a landscape. Multi-shot images are captured as uncompressed RAW files and so can’t be combined in-camera. This has to be done later using the Sony’s new Imaging Edge software.
Due Process
The image processing options for JPEGs start with a collection of 13 Creative Style picture presets. Along with staples such as Standard, Vivid, Neutral, Portrait, Landscape and B&W there are more exotic offerings such as Autumn
Leaves, Clear, Deep and Light.
Adjustable parameters are for contrast, sharpness (now increased to plus/minus five steps) and saturation, with the B&W and Sepia presets simply bypassing the colour controls. The six main presets are repeated as numbered Style Boxes, meaning any adjustment can be saved as a customised Creative Style.
There’s a selection of eight Picture Effect special effects is available which, again, includes the staples such as Toy Camera, Retro Photo, Miniature, Partial Colour and Soft Focus.
Noise reduction is provided for both long exposures and high ISO settings, along with Sony’s long-standing
Dynamic Range Optimiser (DRO) processing and a selection of multi-shot HDR modes. The DRO options comprise auto correction – based on the contrast range of the scene – or five levels of preset correction. An auto bracketing mode is also available for dynamic range expansion processing. The HDR options also include an auto mode – when the camera captures a sequence of three frames with the correction applied automatically (again based on the brightness range in the scene) – and a selection of manually-set exposure adjustments from +/-1.0 EV to +/-6.0 EV, designated ‘Level 1’ to ‘Level 5’.
In-camera lens corrections are provided for vignetting (i.e. brightness fall-off), chromatic aberrations and distortion. The A7R IV has flicker detection and reduction for more stable exposure control when using continuous shooting under gas-ignition light sources (i.e. fluoro types). These actually switch on and off continuously, but at such a high frequency it’s largely imperceptible to the human eye, but can make quite a difference to exposures and colour balance. The anti-flicker function adjusts the shutter’s timing very fractionally during a continuous sequence to avoid this.
Unlike the Mark III model, the A7R IV now has an intervalometer that's programmable for up to 9,999 shots and includes an adjustment for AF tracking sensitivity. Still no multiple exposure facility though.
Points Score
The A7R IV delivers an upgraded hybrid autofocus system compared to its predecessor, employing Sony’s latest AI-based tracking functions. It has 425 contrast-detection AF points and a massive 567 phase-difference detection points to give a combined frame coverage of 99.7% vertically and 74% horizontally – quite a big increase than before. Low light sensitivity extends down to -3.0 EV (at ISO 100 and f/2.0) and there’s a built-in LED illuminator for low light/contrast assist. Switching between single-shot and continuous modes can be done manually or left to the camera when it’s set to AF-A.
A total of four menu pages are devoted to AF functions which include the choice of focus or speed priority
(or a balance of both), and adjustable tracking sensitivity over five levels from ‘Locked On’ to ‘Responsive’.
Autofocus point selection can be performed manually or automatically
via one of five area modes called Wide, Zone, Centre, Flexible Spot and Expand Flexible Spot. The Flexible Spot options allow the focusing zone to be adjusted to one of three sizes – small, medium or large – to better suit the subject matter. In Expand mode, surrounding points are automatically selected if the subject subsequently moves. Continuous AF is supplemented by a Lock-On function that works with any of the area modes to provide more reliable tracking. A focus point or area can be registered for instant recall which is useful when shooting the same scene or subject on a regular basis. Additionally, it can be set to switch position automatically when the camera in used vertically (portrait orientation). You can now also switch the AF frame to red as an alternative to the standard white option. Tracking can be set to face-detect or eye-detect with automatic switching between the two, and also auto switching between the left/right eye detection. This is now using subject recognition processing in real-time (based on a number of factors including colour, brightness and distance) and there’s the option of Human or Animal settings.
Manual focus assist is provided by a magnified view (up to 11.9x) and a focus peaking display that can be set to red, yellow, white or blue (which is new) with three levels of sensitivity (high, mid or low). The focus magnifier can be set to operate continuously or for timed durations of two or five seconds. Handily, it’s also available to assist with determining sharpness when using autofocus.
Light Work
In terms of exposure control, the A7R IV has pretty much the same feature suite as its siblings, but it does get a new mechanical shutter assembly which has improved damping – to help reduce shock and vibrations – and a coreless actuation motor with less inertia (and so delivers a faster response).
Interestingly, Sony rates its new shutter at 500,000 cycles, which is very high, but presumably assumes there will be a lot of shooting at 10fps. The speed range remains at 30-1/8000 second with flash sync up to 1/250 second.
The camera’s sensor-based shutter has the same speed range and there’s the option of the hybrid ‘electronic front curtain shutter’ which starts the exposure with the sensor shutter and finishes it with the conventional shutter. The main benefit is some reduction in vibration and noise (by eliminating the action of the mechanical shutter’s first set of blades) while still allowing for the use of electronic flash (albeit at a lower sync speed). There’s no shutter-delay timer that would allow for all handling related vibrations to die away, but you could use the self-timer’s twoor five-second delay to achieve the same outcome.
The A7R IV has Sony’s Multi
Interface Shoe for connecting an on-camera flash (and other accessories), plus it retains a PC flash terminal at a time when it’s being dropped from other high-end mirrorless cameras. It’s good news if you’re still running off-camera flash units via the traditional cable.
Exposure control is based on in-sensor metering with 1,200 points and the choice of multi-segment, centre-weighted average, fully averaged, highlight biased or spot measurements. The spot meter’s size can be switched between standard or large, and either locked to the frame’s centre or linked to the active focus point or zone. The standard selection of ‘PASM’ exposure control modes are supplemented by a full-auto iAuto mode which, among many other things, performs subject/ scene analysis to fine-tune the exposure settings. Not surprisingly though, there are no settable subject modes.
The auto control overrides comprise an AE lock, exposure compensation of up to +/-5.0 EV (although the dial is only marked to +/-3.0 EV with the additional range accessed via the Exposure 1 menu) and auto exposure bracketing over sequences of three, five or nine frames. For the first two, the maximum adjustment per frame is +/-3.0 EV while over nine frames, it’s +/-1.0 EV. Exposure bracketing sequences can be combined with the self-timer. The exposure compensation dial is now lockable so it can’t be accidentally shifted without you noticing.
White balance control options start with the choice of three auto correction modes – Standard, White-Priority or Ambience-Priority. Alternatively, there are ten lighting presets – including for four different fluoro types and one for shooting underwater – fine-tuning over the blue-to-amber and green-to-magenta colour ranges, plus manual colour temperature setting over a range of 2,500 to 9,900 Kelvin. Three custom WB settings can be created and stored, plus white balance bracketing is available over a sequence of three frames.
In The Hand
It’s still a bit of a mystery why Sony can build its full-frame mirrorless cameras so compact – even with IBIS and a tilt-adjustable monitor – when everybody else is still a bit on the porky side. The A7R IV is still smaller than most APS-C format DSLRs and even some mirrorless models with this size sensor.
The construction comprises magnesium alloy body covers over an alloy chassis with upgraded sealing for better protection against the intrusion of dust and moisture
(presumably now at A9 level). The handgrip is now much deeper so it has a nicer feel and will certainly work a whole lot better when a bigger lens is fitted. The control layout remains centred around a main mode dial (that’s lockable) with front and rear input wheels (the latter now more a dial than a wheel), a fourway multi-selector which also incorporates a control ring, and a bunch of function keys. It’s actually all quite traditional, but also pretty intuitive and efficient. Four buttons are marked C1 to C4 and are customisable, but just about all the other external controls also have this capability, including the multi-selector’s control wheel. Additionally, they can be assigned different functions for when either shooting stills or video, or for playback. There’s also new My Dials customisation for the input and controls wheel, and two on-screen Function Menus – one each for stills and video – comprising 12 function settings. It may sound all a bit daunting, but setting up the customised functions – despite there being up to 113 items across 27 menu pages in some cases – is actually reasonably straightforward. Finally, up to four banks of camera setups – assigned as M1 to M4 – can be stored and three of them assigned to the 1, 2 and 3 positions on the main mode dial.
Of course, you can also create your own My Menu, which is also a pretty straightforward exercise and worth doing when the full menu system runs to 37 pages. As before, touchscreen functionality doesn’t include the menus or the status displays, but there are quite a number of manual navigation options – either of the input wheels, the rear panel controller and the joystick-type controller that's otherwise used for selecting the focus points/ areas. In fact, the touch controls are limited exclusively to autofocusing functions, namely selection or moving of a focusing point, with a ‘touchpad’ option that allows this to be done while using the EVF.
The EVF is a 0.5-inch (1.3cm) OLED panel as before, but the resolution increases to
5.76 million dots and a magnification of 0.78x (35mm equivalent). It’s adjustable for brightness and colour balance plus there’s the choice of Standard (60fps) or High (120fps) refresh rates so the display can be optimised for either increased detailing or faster framing.
The eyepiece has a special fluorine coating to help better repel moisture or grease, and also enable easier cleaning.
The monitor screen is unchanged from the A7R III so it’s a 3-inch LCD panel adjustable for tilt and with a resolution of 1.44 million dots. It’s adjustable for brightness only, but with a Sunny Weather mode for improved viewing in bright conditions. A Quick Navi status display is unique to the main monitor screen and includes a big selection of read-outs and function settings,