Sony Alpha 33
They're being launched as part of Sony's Alpha range, but they're not digital SLRs proper. The new Alpha 33 and Alpha 55 are the first cameras to combine an electronic viewfinder with the phase detection autofocus that is normally reserved for digital SLRs.
If you know the Alpha 5 series, then you won't feel out-of-place picking up one of these new cameras which have broadly the same style and controls. That said, both camera bodies are a good centimetre shorter, a change that photographers with big hands won't appreciate.
Unlike the NEX-3 and NEX-5, the new Alpha 33 and Alpha 55 both have a viewfinder. It's electronic, of course, and could have come straight off a Panasonic G2 or GH1: there's excellent detail and great enlargement of 1.1, which brings it up to almost the same size as the one on the Alpha 850. On the other hand, the contrast is less impressive, and some users perceive a rainbow effect when moving their eyes. The VF-2 found on the Olympus E-P2 is much easier to use. The excellent 3'' VGA screen is the same one as found on the NEX cameras and the Alpha 550, but is now mounted on a bi-directional hinge, rather one at the top and bottom, allowing more room for manoeuvre.
Sony Alpha 55
But it's in video that the new autofocus is most impressive. There's none of the back and forth contrast detection found in camcorders. These new cameras follow fast-moving objects perfectly, and remain trained on stationary objects but resist the temptation to make slight adjustments by moving a little this way or that. And if you move from one subject to another, the focus changes gradually enough to avoid producing a jerky transition.
If you add the 1080i AVCHD video, a built-in stereo mic and an input for an external mic, then the Alpha 33 and 55 could seriously rival your camcorder—especially as they're compatible with all of the Minolta A and Sony Alpha lenses! The only disappointment is that you can't adjust the aperture during recording, and it's inadvisable to beyond f/5.6, the limit for the autofocus.
Taking still photos is much quieter, because the mirror is now fixed. All you hear now is the closing of the shutter, like on the NEX cameras. Note that you can move the mirror manually to clean the sensor if any dust makes it in there, but that shouldn't happen too often as the mirror covers the whole of the inside of the camera.
Taking a photo with a 1/2 s exposure: Canon EOS 550D vs Sony Alpha 55
To differentiate between the two new models, the Alpha 33 has a 14 Megapixel sensor and a burst mode of seven photos per second, but the Alpha 55 has a new 16 Megapixel sensor and GPS, and can photograph at ten photos per second, which is as fast as a Canon EOS-1D Mk IV!
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