Lab Test: Sony Alpha 33 and 55

Imaging through a fixed mirror probably doesn’t help in this department. Still, the images we shot with both preproduction and final production units were pleasingly sharp, even if they don’t maximize the potential of their respective pixel counts.

As usual, Sony keeps noise down even as the sensitivity rises. The A33 showed its lowest noise levels at ISO 200 and ISO 400, with scores of 1.9 for Low ratings. Still, we often see scores closer to 1.1, our cutoff for an Extremely Low rating, with a recent example being Canon’s Rebel T2i. Stepping up to the A55, you’ll get those lower noise levels, matching the Rebel T2i’s Very Low scores at ISO 100 and 200. The A55 remained very competitive with the T2i throughout their shared sensitivity range of ISO 100–12,800, though both cameras reached Unacceptable levels at their highest ISOs. But then again, the 18MP Canon also delivered 2555 lines of resolution and Excellent color accuracy. So, while both cameras give up resolution as ISOs increase, the Canon has more to spare.

One area where the Rebel T2i can’t match either the A55 or the A33, though, is AF speed—and that’s exactly the point of the new mirror system. Both Sonys were able to focus extremely fast, with some of the best AF test results we’ve seen this year—truly rare performances for midrange cameras. At the brightest three levels of our test (EV 12, 10, and 8) they locked focus and captured an image in 0.30 seconds or faster. Even at the near-moonlight darkness of EV –1, the two models focused in under a second (0.82 for the A55 and 0.84 for the A33). Both slowed to just slightly more than a second at EV –2, but Sony rates them to focus down only to EV –1, so we were surprised that they focused at all in that darkness.

Furthermore, both cameras did an excellent job of tracking subjects as they moved toward or away from the camera. Sony says that these models can track a subject moving toward the camera at high rates of speed. After shooting a variety of moving subjects, including cars in Manhattan and trains speeding through stations, we believe Sony’s claim.

In the Field
Thanks to the lack of an optical finder, these models aren’t quite as tall as a normal DSLR, though the housing of the EVF and AF module provides a very DSLR-like look. And, since there is a mirror, these cameras are deeper than the mirrorless ILC cameras that have been hitting the market lately. They're quite light, just over a pound each, including battery and a memory card. That also means that with a heavy lens, you’ll end up with a noticeably front-heavy rig. With the kit lens, though, they are well-balanced and comfortable to hold.

The bodies have only one command wheel—a shame for manual shooters, because changing the aperture is a clumsy affair of a simultaneous press of the exposure-comp button while turning the command wheel. And since that button is mounted on a downward angle, it makes this operation difficult to do single-handed.

The camera’s grip itself is well contoured, with a nicely defined spot for your middle finger and an unusually deep divot on back for your thumb. The entire grip area is covered in textured rubber. We would gladly have given up some of that rubber to have a dedicated SD card slot instead of the bottom-loading slot in the battery compartment.

Most of the camera back is dominated by a 3-inch, 921,600-dot LCD screen that flips downward and rotates up to 270 degrees. It doesn’t leave much room for dedicated control buttons, but you can access display mode, white balance, drive mode, and ISO using the round control pad.

The Function button above that pad brings up a menu of all of the most commonly changed settings. It’s a decent system, and thanks to the EVF, you don’t have to take your eye away from the finder to change any of the settings, even those that can be adjusted only through the main menu. Strangely, the cameras’ sensor-shift image stabilization is in the main menu, while face detection is in the Function menu.