The 12.25-megapixel Sony Alpha A700 is the second digital SLR the Japanese electronics giant has launched and is aimed at the serious enthusiast.
The first hint of what what was to follow came with the company’s announcement of its commitment to CMOS sensor development, followed by the announcement of a new sensor, with a potential burst rate of 10.39fps, built on CMOS technology.
And now we have the outcome – the Sony Alpha 700 – a camera built to semi-pro specifications, with a host of new and improved features. Do Canon and Nikon have anything to worry about?
Firstly we need to talk about that sensor. The original IMXO21 code name has been changed to the more market-friendly ‘Exmor’, and the chip contains 13.05 million pixels, giving an effective count of 12.2MP. The APS-C-sized sensor offers a revolutionary on-chip A/D conversion system, which works to reduce noise in a different way from most sensors.
Usually the signal from the sensor moves down an electronic pipeline to the processor, which introduces noise as the signal leaks on the journey. The processor performs the Analogue/Digital conversion (A/D), including signal amplification to raise the ISO: if necessary – another noise introduction – and performs the appropriate image processing such as white balance, sharpness, colour, etc.
The Exmor’s built-in circuitry performs the analogue noise reduction before the A/D conversion, then performs digital noise reduction, and further noise reduction is performed inside the Bionz processor. The result is, according to Sony, better noise control even at high ISO:. On top of all that, more noise reduction is applied at sensitivities from ISO: 1600. Incidentally the camera’s top sensitivity is ISO: 3200 with a boost option up to ISO: 6400.
The initial announcement made claims that the sensor can record at 10.39fps, however the A700 manages only 5fps to the capacity of the card in normal JPEG mode. Still, it offers us a glimpse of the future, and not just from Sony, as it may well sell this chip to other manufacturers as it has in the past.
Konica Minolta’s pioneering of sensor-based image stabilisation is continued under the Sony umbrella using the Super SteadyShot feature, which the company claims is improved further on the A700. Sony now states the user can shoot at between 2.5 and four stops slower shutter speeds than on a non-IS camera, so at 200mm for example, instead of shooting at 1/250sec, you could hold the camera at 1/15sec to 1/45sec and still maintain sharpness.
Built into the image stabilisation is a dust-protection system, whereby the sensor vibrates at high speed to dislodge any dust. Unlike other systems, this system kicks in when the camera is turned off, so enabling a faster start-up time. An anti-dust coating on the low pass filter to reduce static (and so reduce the chances of dust clinging to the sensor in the first place) augments the sensor vibration.
Dynamic Range Tool
Another improved feature of the Alpha is the Dynamic Range tool which expands the capacity for recording extremes of highlight and shadow. The system offers a choice of three modes – standard, auto and selectable – with a choice of five levels of enhancement.
Exposure Metering and AF
Sony has also revamped the metering, with a 40-zone honeycomb metering, along with spot- and centreweighted metering. The auto focus system is revamped, with a new centre dual-cross 11-point AF. A new AF sensor promises greater focusing accuracy at wide apertures.
Usefully the camera features a PC socket for using studio or off-camera flash, while a built-in flash offers a GN of 12m @ ISO: 100 and a hotshoe allows the use of Sony-compatible flash units. Flash sync speed is set at 1/250, dropping to 1/200sec in SteadyShot mode.
Images are saved to Compact Flash, while a secondary slot accepts MS Duo cards, and the camera has a wide choice of recording formats, including 12-bit Raw and Raw+JPEG. Sony has introduced a new format into the mix in the form of cRaw, or Compressed Raw, which reduces the size of the image file by around 30%. The buffer can hold 25 cRaw files rather than 18 in full size Raw. Sony and Adobe are co-operating to allow the new file to be supported in the next update of Adobe Camera Raw software. For now, only the included Sony software can open the files.
The software includes a tethered shooting option, giving remote control of the camera via a PC or Mac, which is useful for some studio work or for controlling the camera in tricky locations. The camera also comes with a wireless remote control, allowing shutter operation when shooting.
Build Quality and Styling
The build quality of the Alpha 700 is of a high standard. Constructed from magnesium alloy, Sony has also added dust and weatherproof seals to the exposed areas such as buttons and the dial. It isn’t to the build standard of true high-end pro cameras such as the Canon 1D series, and wouldn’t necessarily trust it to survive a three-month tour of the Belize rainforests, but it’s comparable to the new Nikon D300 and Canon 40D and survived a heavy downpour in Essex with no trouble.
The styling isn’t to everyone’s taste, continuing the slightly boxy design typical of Konica Minolta cameras, but it’s ergonomic grip and button placement make it a pleasure to use. Everything falls easily to hand. A pair of raised areas on the front of the grip, and at the rear provides security for the thumb and middle finger.
The right-hand top-plate is sparse, with just four buttons, plus the shutter release button. These buttons, controlling ISO:, WB and drive modes are fiddly to use: the grip is too deep for the forefinger to reach them comfortably. Sony has switched some features from the Sony Alpha 100 away from the left-hand dial to the back, so you no longer need to turn the dial to access the ISO: and DR tools, like you had to on the Sony Alpha 100. This leaves the dial free for the exposure modes, which include the standard PASM group, as well as a selection of scene modes and the Memory Recall or ‘custom’ mode.
The camera has some lovely touches. The viewfinder is nice and bright with a good eye point. We found it easy to see the whole frame and read the LCD readouts even with glasses. Like the Sony Alpha 100, the new model features Eye-Start AF, which is a useful feature but can result in the camera being accidentally left switched on when walking around. This means the Eye-Start sensor, situated beneath the viewfinder, is constantly activating the AF as the camera rubs against the body, running the battery down. Luckily a menu option lets you turn the sensor off.
The AF is better than on the Sony Alpha 100, with eleven selectable sensors and rapid operation. Using a Carl Zeiss 16-80mm lens in this test, the AF is also pretty quiet. We really appreciated the thumb-friendly AF/MF button. When this is pressed, you can manually focus the lens for fine-tuning. Its position is really well thought out and it’s a truly useful and thoughtful touch.
A welcome addition is the new shutter. Where the Sony Alpha 100 shared the Konica Minolta 5D’s clunky shutter, the A700 has a much quieter, dampened shutter and with shutter speeds available up to 1/8000sec. Sony also claims that the shutter has a service life of 100,000 operating cycles.
Even with Sony’s claims about the new sensor taken into account, noise control pretty impressive. At ISO 100 and 200 the images are silky smooth – as might be expected. Noise is barely visible at ISO 400 and 800 either, and only if you look closely into shadow areas.
At ISO 1600, noise is just about visible, but on a par with that of around ISO 800 on an average DSLR. From there, the camera goes into boosted ISO, and even here the lack of noise is remarkable. Yes there’s chroma noise, but it’s very well controlled, and the images lose very little sharpness – a typical side effect of over-eager noise reduction.
A 12MP chip should theoretically produce sharper images, as detail is more tightly recorded on the individual pixels. This is certainly the case with the A700, especially when used with the excellent Carl Zeiss 16-80mm lens.
On a slightly less positive note, the SuperSteadyShot is not always effective. On average it produces good results, but there are times when even at 1/60sec there’s still signs of camera shake. This is more prevalent when shooting continuously.
Tone And Contrast
The sensor mostly performs well. High-contrast scenes such as low afternoon sun can cause some highlight burn out, but that can be expected that with most mediums. On the other hand, the sensor manages to retain good shadow detail, and with careful exposure, most subjects can be recorded faithfully. The Dynamic Range Optimiser is there for trickier subjects, such as bright skies, and the improved version in the A700 knocks spots off the Sony A100’s. We like the natural look of images, compared to Nikon’s D-Lighting system which can look forced.
Colour And White Balance
With a full set of clear colour modes, there are endless choices to customise your camera, and colour reproduction from the Sony is very good in Raw and JPEG mode. White Balance occasionally needs a tweak, which is not unusual, if you’re a real stickler. The option to control colour using the Kelvin scale, or manually, or via tint controls, will fix most problems. Or shoot Raw and make post-processing corrections.
There’s very little to complain about on the Sony Alpha 700. The time spent with it was an absolute pleasure – we found it very intuitive. Everything you need is easily to hand, so you can concentrate on picture taking rather than scrolling through menus.
Images have excellent resolution and good exposures and tone. Auto-exposure and autofocusing are pretty much faultless, and on the rare occasions when they do get it wrong, the Sony has all the tools available to fix things.