Sony Alpha 99 at a glance:

  • 24.3-million-pixel, full-frame, Exmor CMOS sensor
  • Fixed translucent mirror design (SLT)
  • ISO 100-25,600 (extended to ISO 50)
  • 2.359-million-dot XGA OLED EVF
  • 3in, 1.228-million-dot dual articulated LCD screen
  • Dual AF system with 19-point phase detection and 102-focal-point sensor
  • 10fps high-speed burst shooting
  • Weather-sealed magnesium-alloy body
  • Street price £2,299 body only

Sony Alpha 99 review – Introduction

A lot has changed during the four years between the launch of Sony’s original flagship full-frame DSLR, the Alpha 900, and the arrival of its replacement, the Alpha 99. While both use the same lens mount and a full-frame sensor with an approximate 24-million-pixel resolution, there are few other similarities. The launch of the Alpha 99 means that Sony’s current Alpha range is made up entirely of SLT (single lens translucent) models rather than DSLRs. So, from the entry-level Alpha 37 through to the Sony Alpha 99, all the cameras use a fixed translucent mirror rather than the moving mirror set-up of a traditional DSLR.

When SLT technology was introduced two years ago in the Alpha 33 and Alpha 55, we went into detail about the impact this set-up has on the handling and image quality of the cameras (AP 9 October 2010), and the same information applies to the Sony Alpha 99. A fixed translucent mirror set-up works by allowing approximately 70% of the light through to the imaging sensor, and redirects the remaining 30% to an AF sensor.

Benefits of the SLT system over the direct competition include full-time live view and phase-detection AF, and fast frame rates because the mirror is fixed and does not need to move between frames. However, there is a concern about the impact that a 1/3EV reduction of light reaching the sensor has on image quality, particularly in low-light performance. Also, as only 30% of light would be directed to the viewfinder, an optical type would be too dark so an electronic viewfinder (EVF) is used instead.

Recently, Sony has been one of the leading innovators in new camera technology, and this in turn provides unique selling points for its cameras. These will be crucial as the company tries to include the Alpha 99 into a professional market long dominated by competitor brands. The Sony Alpha 99 is up against the likes of the Canon EOS 5D Mark III and Nikon D800, so it will have to offer something that its rivals don’t.

To this end, the company has been working hard, particularly on the Alpha 99’s autofocus, and on paper everything looks very good. However, the true test is when the camera is in the hand. I am therefore keen to see how the Alpha 99 performs in the sorts of situations a professional would use it, and whether Sony’s SLT technology is appropriate for this market.

Sony Alpha 99 review – Features

Image: With the Sony Alpha 99’s fixed mirror there is little camera shake during capture, which benefits long exposures. This image is pin-sharp 

The Alpha 99 uses a 24.3-million-pixel, Exmor CMOS sensor with a fixed translucent mirror, but it’s a full-frame size, which means it has a large surface area to collect light and its photodiodes are physically large. This should result in a significantly better low-light performance than that of the Alpha 77, which has the same pixel count but uses a smaller APS-C-sized sensor.

Sony claims that the Alpha 99 has more than twice the saturation, one and a half times the sensitivity and a 50% reduction in noise in like-for-like images taken with the Alpha 900. Given that the full-frame Alpha 900 has a similar resolution but uses a more traditional DSLR mirror mechanism without 1/3EV light reduction on the sensor, we can see just how much more efficient Sony claims to have made its sensors. Factors include what the company claims is a thinner wiring layer between the on-chip lens and photodiode, allowing more light to reach each photodiode. Also, a newly developed ‘multi-segment’ low-pass filter is claimed to let more light through than a conventional low-pass filter would, so we should expect sharp images, too.

A new Bionz engine produces 14-bit raw files. This processor uses the same adaptive noise reduction as Sony’s Cyber-shot DSC-RX100, which works by analysing the picture detail, be it edge or texture, and then applying more noise reduction to parts of the frame where detail is not as important and less to where detail is crucial.

The Alpha 99 features sensor-shift SteadyShot for image stabilisation up to an effective 2.5-4.5EV. Having this feature in-camera means that Sony Alpha and Konica Minolta lenses do not need stabilisation built in. Also, in using a fixed mirror, the Alpha 99 is not affected by the shake caused by mirror-slap, which the Alpha 900 suffers from. There is therefore no need to include a mirror-lock drive mode.

Phase-detection AF with 102 focal points is built into the imaging sensor, working alongside the 19-point phase-detection AF sensor. Sony has introduced a new AF mode (AF-D) that uses both these systems together. I will go into more detail about this later.

There are a number of shooting modes, including an 8fps and 10fps tele-zoom high-speed burst (see High-speed Shooting). Bracketing is available for the Dynamic Range Optimizer (DRO) and white balance over three consecutive frames, while bracketing for exposure up to ±3EV is possible across up to five frames.

Image: An exposure at +3EV is around the limit for crisp detail in shadow areas

The HDR mode is available in JPEG only and records over three frames up to ±6EV, but the frames are recorded consecutively so a tripod is advised. Other modes include the sweep panorama, while the teleconverter enables a 1.4x or 2x focal-length magnification at a reduced file size. It would be nice to see multiple-exposure and time-lapse modes included, as many other high-end models feature these.

Sony Alpha 99 review – High speed shooting

Impressive as they sound, each of the 8fps and 10fps tele-zoom high-speed burst modes on the Alpha 99 is available in JPEG format only, at medium or low quality respectively, and with autofocus and exposure locked from the first frame. For full-resolution raw and JPEG images, and with exposure and AF control during a continuous high-speed burst, the continuous high mode offers a reasonable 6fps rate.

In good light and using a low ISO, continuous high provides a burst in excess of 20 frames in JPEG format only, which is solid. In low light with high ISO settings, the increased application of noise reduction reduces the number of frames in a burst. Having used the Alpha 99 for a low-light floodlit football match, the number of frames in a burst was not enough to capture passages of play, getting ten frames at best. Reverting to the more responsive tele-zoom high-speed burst, the lack of exposure control is frustrating. I found the camera often opted for shutter speeds too slow to freeze the fast action. So, while the camera’s autofocus performs well, it is not backed up by an effective high-speed shooting capability in low-light conditions.

Sony Alpha 99 review – Build and handling

Those familiar with the Alpha 77 should quickly feel at home with the Alpha 99. Both are constructed to a high standard with a weather-sealed body, magnesium-alloy chassis and front panel made of tough plastic. As the Alpha 99 is the lightest full-frame camera and one of the smallest, a long day’s shoot can be comfortable, too. Despite its small dimensions, using heavier and chunkier professional lenses, such as the Carl Zeiss 24-70mm f/2.8, does not throw the balance of the camera.

A look at the Alpha 99’s rear reveals a button layout very similar to that of the Alpha 77, although the buttons are less ‘clicky’ in use and beautifully dampened, as one would expect from a professional camera. Additions include a new AF range button, which accesses the new autofocus limiter function. On the front of the camera is a ‘silent controller’. This is, in effect, a new function dial primarily designed for video users, although controls can be assigned to it separately for still image and video capture. In fact, the functions of most of the buttons on the camera can be changed to control other settings, although there is little point in changing the ISO button to another control other than ISO.

A shooting-mode dial includes the usual PASM settings, as well as three custom settings, auto, scene, panorama, video, plus the tele-zoom high-speed mode. There is a lock button in the centre of the dial, which must be pressed in order to turn the dial. The dial is firm already, but the lock is reassuring.

Sony has changed the accessory shoe to the standard type rather than its own Konica design that is used in all other Alpha cameras. A new flashgun, the HVL-F60M, has therefore been announced alongside the camera, but those with older Sony flash units will need to use an adapter (supplied with the camera) to attach older units to the camera.

On the underside of the camera are the necessary contacts to connect the new ‘chimney-less’ battery grip. Even with the grip attached, the in-camera battery can stay in place and there is space for two extra batteries in the battery grip. With three camera batteries in place, Sony claims a battery life of up to 3,200 shots, which is impressive. However, that’s without the GPS function activated. When GPS is on, or for those who often shoot AVCHD videos, the battery life is significantly less than the quoted figures.

There are a couple of handling issues that need to be addressed if the Alpha 99 is going to compete fully at this level. For instance, start-up time is slow, with the controls, top LCD, viewfinder and rear-screen displays taking around 3secs to ready themselves. When turning the exposure dial, there is a minor lag in this information on the display, which can be a little frustrating. Most of the camera’s navigation is achieved using the joystick on the rear, which is responsive and easy to use. Throughout the test the joystick has been fine, but I do wonder how it will cope with bumps, knocks and extended use.

I would like to see some basic in-camera edits included, such as colour modes and cropping. Currently, rotation is the only possible edit, while in some other camera systems there is even raw file editing. Also, there is no way to rate images in-camera, which is a shame as this is a handy tool when out and about, to make a quick reference rather than scrolling through a large number of images at the end of a day’s shooting to find favourite shots.

All in all, though, the Alpha 99 sits well in the hand, is well constructed and its level of customisation makes for speedy navigation.

Sony Alpha 99 review – White balance and colour

All the Sony Alpha cameras I have used typically have a punchy colour rendition when set to the standard colour mode, and the Alpha 99 is no different. I rarely choose the more muted natural or highly saturated vivid colour modes, as I am usually satisfied with the standard setting. I find that in the standard setting blue skies are punchy, as are greens in a landscape, but I did enjoy using the vivid setting when photographing colourful beach huts. There are a few extra colour modes available, namely autumn leaves, deep and sunset. Each of the colour modes can be adjusted for saturation, sharpness and contrast. I suspect the professionals and serious enthusiasts at whom the Alpha 99 is aimed are less likely to dabble with the picture effects, which include toy camera, high-key and partial colour, and which are available in JPEG capture only.

There are no surprises when it comes to the accuracy of the white balance system. AWB is, on the whole, reliable, but one must be wary of the usual scenes that may trick the colour rendition, typically where a single colour dominates a scene.

Image: There are a number of colour modes, all of which are available pre-capture and only in-camera. The six below are likely to be the most commonly used

Sony Alpha 99 review – Metering

The Alpha 99 uses the same 1,200-zone evaluative metering system as that found in all Sony’s SLT cameras, so it is a system we are very familiar with. Its evaluative mode is predictable, which is useful once one understands how it behaves. In high-contrast scenes where there is an equal share of light and shadow areas, the system leans towards a bright exposure, so it can be worth dialling in underexposure to ensure highlight detail is maintained. Otherwise, for predominantly dark or bright scenes, the evaluative mode can be relied upon.

For scenes that can trick the metering, such as a backlit portrait, the system is not quite as sophisticated as that found in the Nikon D800, which links functions such as face detection to the metering. With this in mind, spot metering can be useful to ensure an accurate exposure. It can be linked to the active AF point on the 19-point phase-detection AF sensor, which is unfortunately limited to a small central area of the frame, so recomposing may be necessary for off-centre subjects.

Sony Alpha 99 review – Noise, resolution and sensitivity

These images show 72ppi (100% on a computer screen) sections of images of a resolution chart, captured using the fixed Carl Zeiss 24-70mm f/2.8  lens. We show the section of the resolution chart where the camera starts to fail to reproduce the lines separately. The higher the number visible in these images, the better the camera’s detail resolution is at the specified sensitivity setting.

Unsurprisingly, when compared to the Alpha 77 with the same pixel count, resolved detail in the Alpha 99 is equal in good-contrast light at ISO 100 – up to the 32 marker on our resolution charts. There is a significant improvement in the low-light performance of the Alpha 99, though, and the camera can still resolve up to the 26 marker at its ISO 25,600 setting. In fact, the sensitivity range is wider at 9EV to 813EV, where the Alpha 77’s maximum setting is ISO 16,000.

I am interested to see if the Alpha 99’s low-light performance matches the Cyber-shot DSC-RX1, which uses the same full-frame sensor but is a mirrorless camera without the 1/3EV light loss that occurs with a fixed translucent mirror. In a similar comparison with the Alpha 77 SLT camera and the mirrorless Sony NEX-7, the NEX-7 performs better in low light.

Although the camera scores well on our charts, JPEG files shot at ISO 3200 and above are not especially crisp. When viewed at 100% they are mushy, with chroma noise evident as well as the expected luminance noise. Raw files are sharper, though, so it is definitely worth using raw capture, especially in low-contrast light.

Sony Alpha 99 review – Autofocus

This diagram shows the 19-point phase-detection AF sensor array and the 102-point focal-point array. Sony claims the latter covers 30% of the frame

Sony has introduced some interesting changes to the autofocus set-up of the Alpha 99. It uses a dual phase-detection autofocus system. Like the Alpha 77, the phase-detection AF sensor is made up of 19 points, 11 of which are the more sensitive cross type. These 19 points are grouped together in a small central portion of the frame. For quick and successful focusing across a number of situations and light conditions, it is key for the subject to be covered by the cross-type points. There is a further focal-point sensor with 102 points that is built into the imaging sensor and has an approximate 30% coverage of the frame, which is impressive.

To complement the new dual AF set-up, an AF-D mode has been introduced, which uses both systems. This mode works well with object tracking for fast-moving subjects such as football players, but also for landscapes or subjects that are off-centre as the AF point coverage is wide. It should be noted that the dual AF is only available with six current lenses, including the Carl Zeiss 24-70mm f/2.8 lens used in this test, although Sony promises firmware upgrades for more lenses.

A handy feature is the new AF range control, which offers manual control of the minimum and maximum focus distance. There are a couple of benefits to limiting the focus range – subjects nearer to or further away from these distances do not confuse the AF system, and there is less distance for the camera to scan for a focus point, which means quicker focus in low-contrast light.

For subjects in the centre of the frame, the Alpha 99 performs excellently. I do, however, find the limited coverage of the 19 points to the centre portion of the frame more restrictive for spot focusing.

LCD, viewfinder and video

When I tested the Alpha 77 it had the best EVF around, with smooth, crisp and vivid detail. I even went as far as to say that at times it is easy to forget it is an EVF rather than an optical type. The Alpha 99 also uses an XGA OLED EVF with a 2.359-million-dot resolution, 100% field of view and 0.71x magnification. A direct comparison of the two EVFs shows that the Alpha 99 has marginally improved on the Alpha 77. Detail is even smoother, and the display is less ‘vivid’ and more ‘authentic’.

In good-contrast light, the auto setting of the EVF display is a little darker than the optical viewfinder of the Alpha 900. It is worth manually brightening the display to its brightest setting (+1). In low-contrast light, however, the EVF is generally more useful than an optical type because its display can automatically be adjusted to brighter than real life. Also, exposure preview is undoubtedly handy, showing changes to exposure such as white balance. The colour temperature of the display can be adjusted, and at times I found the overall temperature a little cool, so I adjusted it to -1. In certain situations, moiré patterning can be seen in patterns such as a brick wall.

There is an eye sensor below the viewfinder to automatically switch between displays, and AF can be performed each time one places the finder to the eye.

These auto controls can be deactivated. Like the Alpha 77, the 3in LCD screen of the Alpha 99 features a unique tilt-and-swivel design, which is the most versatile camera screen I have used. The screen is articulated from a hinge on its underside, which is in turn attached to a tilt plate that comes out from the camera body. Combining the tilt and swivel allows for LCD viewing above from the camera’s front. The resolution of the screen is 1.228 million dots, which includes a white pixel for every red, green and blue pixel to improve the brightness of the screen. We have seen this set-up in Sony’s Cyber-shot DSC-RX100 and it is indeed bright.

Video users are well catered for, with full HD 1080p recording possible at 24fps, 25fps, 30fps, 50fps and 60fps. Sound levels can be monitored using the audio level display, and there is support for XLR and a separate headphone and microphone jack. Video output, as well as live view to an external screen, is possible via the HDMI port.

Dynamic range

Image: At its highest setting (Level 5), the DRO produces HDR-like results

The Alpha 99 is able to capture a wide range of tones in a single frame. There are additional settings that can be used to extend the dynamic range or to boost highlight and shadow detail in-camera rather than in post-production.

Sony users will be familiar with DRO, which is designed to make detail over a wide range of tones more obvious, and is usually most noticeable in the brightening of shadow areas. Most camera systems offer this feature, but this does not extend the dynamic range. Instead, it merely makes the information that is already there more obvious.

DRO can be adjusted for up to five levels of strength, with the strongest setting (Level 5) producing HDR-type effects, where the tones are boosted too much and the end result is flat. I find leaving DRO in its auto setting to be acceptable. The HDR mode is designed to extend the dynamic range up to 6EV. Given that the dynamic range is in the region of 13EV, a total range of 19EV is possible.

The competition

Image: Nikon D800 

The Alpha 99 competes against the likes of the Nikon D800 and Canon EOS 5D Mark III, which makes its retail price good value at around £300 and £500 less respectively. The use of a fixed translucent mirror means there are several differences between the Alpha 99 and the competition, especially in the handling.

The Alpha 99 is the lightest full-frame, DSLR-style camera around, which helps for a long day’s shooting. It is the only camera in its group with an articulated screen, and with an EVF. Thankfully, the EVF provides an authentic viewing experience, with the benefit of exposure preview and manual-focus aids.

Image: Canon EOS 5D Mark III

As for handling, the start-up time, lag in some controls and slightly deceptive specification on fast frame rates means the Alpha 99 does not quite compete at this professional level.

Our verdict

On paper the Alpha 99 reads well, and for the best part it is impressive in the hand, too. It is made to a high standard, its LCD screen and viewfinder are easy to use, and there are useful additional accessories available, namely the battery grip that can extend the battery life threefold. Landscape photographers should also appreciate how the fixed mirror reduces camera shake. However, the start-up time can be a hindrance.

When compared to the Alpha 77, the low-light performance of the Alpha 99 has been improved no end, and in most respects this is the best Alpha to date. As for the full-frame competition, the Alpha 99 is one of a kind. It is built to a professional standard, yet offers the same shooting modes and picture effects as the company’s entry-level SLT cameras. Thankfully, though, its image quality stands the test, as does its autofocus system, especially the new AF-D mode. However, when it comes to the high-speed shooting situations, there are other pro cameras that offer more control.

Sony Alpha 99 – Key features

Accessory shoe
For the first time in a Sony Alpha camera, a standard hotshoe mount is used rather than the company’s own Konica Minolta thread

Memory card
The Alpha 99 uses twin SD card slots, and Slot 1 also accepts the Memory Stick Pro Duo card type

As with most of the buttons, the teleconverter button can be customised. In this case, it is between teleconverter control (1.4x and 2x) and manual-focus magnification

AF range
This new
button accesses the AF range function, where the minimum and maximum focus distances can be manually adjusted to stop objects outside the focus area confusing the autofocus

All images can be tagged with GPS information through the built-in GPS unit. It can be turned on or off, as can the auto time-correct function.

Whereas the Alpha 77 offers a mic input only, the Alpha 99 also has a headphone jack so both devices can be simultaneously attached to the camera. Sound levels can therefore be monitored not just on-screen, but also via headphones.

The electronically controlled focal-plane shutter has a maximum speed of 1/8000sec through to 30secs and bulb, and is tested to 200,000 cycles. The maximum flash sync speed is 1/250sec.

A key accessory is the VG-C99AM vertical grip (£299.99), which duplicates the grip for vertical shooting and can hold an extra two batteries. Not only was the new HVL60M flash unit (£459) announced alongside the Alpha 99, but also an (included) adapter to attach other Sony flash units to the new standard hotshoe mount.