Sony Alpha NEX-5

Noise Reduction (6.95)

Like the Sony A550, the NEX-5 doesn’t offer the same level of control we find on most manufacturers’ SLRs, which let you turn off high ISO noise reduction processing altogether. The NEX-5 has two settings: weak (the lower level of processing) and auto (the higher level). In our lab testing, there really isn’t a lot of difference between the two, even at the highest ISO settings. The potential problem with high ISO noise reduction processing is the loss of fine image detail. In our test photos, though, we found little evidence of this. More on how we test noise.

Under bright studio lighting the NEX-5 did very well in our image noise testing. As expected, the Micro Four Thirds cameras had problems here when compared to the APS-C models, which hold up well even compared to many pricier SLRs.

ISO Options

The NEX-5 offers ISO settings from 200 to 12800. When using Auto ISO, the setting tops out at ISO 1600.

The chart below shows same-size crops taken from our still life photos, which are shot in program mode with automatic white balance, with noise reduction turned off. These images are not used in our actual scoring, which is based on photographing a standardized test chart.

Focus Performance

A key concern when evaluating mirrorless cameras versus SLRs is autofocus speed. A key reason to include a mirror in an SLR is to bounce light to a dedicated autofocus sensor that uses fast phase detect technology. Without a mirror, autofocus is based on data taken directly from the image sensor itself, evaluating different lens positions to figure out which setting offers the highest contrast (which equals the sharpest focus).

We have yet to find a mirrorless model that can match the autofocus performance of even an inexpensive SLR. The Sony NEX cameras come surprisingly close, though, and that’s a key competitive advantage, particularly against the Olympus Micro Four Thirds cameras, which even after a recent firmware upgrade are the slowest of the bunch.

The NEX-5 offers two focus modes: Single shot, where the camera focuses and maintains focus while shutter is half-way pressed, and continuous autofocus, where the camera continues to adjust focus as long as the shutter is pressed half-way.

The camera can be set to autofocus, manual focus or what’s called ‘direct manual focus,’ which uses autofocus and then allows manual adjustment while the shutter button is depressed halfway.

There are three focus area options:

• Multi – Camera chooses from 25 AF areas.
• Center – Only the center focus point is used.
• Flexible Spot – User selects the AF point to be used by moving the four-way controller.

When shooting in Intelligent Auto mode, apertures can be adjusted without dealing with that messy technical term. The ‘background defocus’ screen is accessed by pushing the middle control wheel button. Turning the wheel in this mode lets the user adjust background sharpness, on a scale from Crisp to Defocus. There’s no information presented to help users learn the aperture control concept, but the on-screen display does offer live depth of field preview, so you can see the effect as you turn the wheel.

The front lamp next to the hand grip functions as a self-timer indicator, and also as a bright, effective autofocus illuminator.

The face detect capability, which recognizes up to eight individuals, is based on the Sony point-and-shoot system. In addition to standard face detect, you get child-priority and adult-priority modes, which are self-explanatory. There’s also a Smile Shutter function; after pushing the shutter, the camera waits until it detects a smiling face before taking the picture (if everyone’s feeling morose that day, you can just press the shutter a second time to take a shot). And depending on the level of jolly you desire, there are three sensitivity settings for the smile shutter feature; Big Smile, Normal Smile and Slight Smile.

Long Exposure (8.47)

Our long exposure testing takes into account both image noise and color accuracy results when shooting at slow shutter speeds. The Sony NEX-5 performed reasonably well in the image noise testing, but its color accuracy problems carried over when the lights were turned down low, producing a middle-of-the-road overall score for this section. Both of the Micro Four Thirds cameras in our comparison group scored lower, based on poor image noise performance. Both of the other APS-C-format cameras scored higher overall. The Samsung had higher color error than the Sony but much lower noise. The two Sony cameras were about even when it comes to color error, while the A550 noise performance falls between the NX10 and the NEX-5. More on how we test long exposure.

Color error was slightly higher when long exposure noise reduction processing was turned on. In terms of doing its appointed job, though, the long exposure noise reduction had virtually no effect. Best bet: just turn it off.

If you’re planning to shoot the creatures of the night, there are better choices than the NEX-5, but performance is acceptable in this area.

Video: Low Light Sensitivity (6.30)

The Sony NEX-5 surprised us with a solid performance on our low light sensitivity test. The camera needed 11 lux of light to hit 50 IRE on our waveform monitor, which is less than half the amount of light required by many video-capable DSLRs to reach the same levels. We have seen some consumer camcorders and high-end video-DSLRs with better low light sensitivity than the NEX-5, but this is still a very good performance from the camera.

Other than the NEX-5, all of the cameras in this testing set record using 30p frame rates, although the Panasonic GF1 also has a 720/60p option. Since one of the primary assets of a video-capable DSLR is the fact that you can use interchangeable lenses, you should remember that much of what determines low light sensitivity is based on the speed (aperture) of the lens used with the camera. The numbers from all of our testing were obtained using the kit lens with the Sony NEX-5.