With its SLT series of cameras, Sony spans a gap between mirrorless Interchangeable Lens Cameras (ILCs) like the Olympus PEN series, Panasonic's Lumix G series, and Sony's NEX models and Samsung's NX series and traditional dSLRs. The defining difference between the two categories is a mirror: in ILCs, light travels directly through the lens to the sensor, while in dSLRs, the light is either reflected up into the viewfinder by a mirror or allowed to directly hit the sensor for capture if the mirror is flipped up. The SLTs have a fixed, translucent mirror--hence it lacks the "reflex" of an SLR--which splits the light path.
Also known as a pellicle mirror, a TM passes most of the light from the lens through a fixed semitransparent mirror, reflecting a small bit of the light upward to a separate phase-detection autofocus sensor. This is how Sony achieves the faster phase-detect continuous AF for movie capture, while most current ILCs and dSLRs use the slower contrast AF, which is based off the imaging sensor. It also means that the camera can achieve the faster still-photo autofocus speeds associated with dSLRs.
One doesn't necessarily need to use a mirror to incorporate phase detection, though; for example, Fujifilm's recent F300EXR point-and-shoot uses a phase-detection array layered over the image sensor. Because many older dSLR-mount lenses can only work with phase-detection AF--that's why ILC adapters for older lenses generally don't support AF--Sony's system enables autofocus when using those lenses for shooting video.
The trade-off is in the viewfinder, however. Unlike a dSLR, but like some ILCs, the SLT uses an electronic viewfinder. That's because the amount of light reflected up to the phase-detection sensor isn't enough to sufficiently illuminate a dSLR-like optical viewfinder. So the shooting experience of the SLT-A55V is a kind of hodgepodge as well. And because the mirror doesn't perform the single most important function it serves in a dSLR--enabling an optical viewfinder--we categorize the SLTs as ILCs rather than as dSLRs as Sony's marketing does.
I have mixed thoughts about the A55V's photo quality. By many objective standards it fares pretty well for its price class. In JPEGs up through ISO 1,600 it does a decent job balancing noise and detail. At ISO 3,200 photos look acceptable unless you've got a lot of fine detail or edges where softness will be too obvious. I find you can get sharper results with more attractive grain by processing the raw files, but the trade-off is more clipping in the shadows; there doesn't seem to be a lot of dynamic range to play with. For high ISO sensitivities, Sony has vastly improved its noise-reduction feature in recent cameras. While there are still some obvious artifacts, there's a much better balance between sharpness and color noise reduction than I'm used to seeing in photos shot with older models. And I was pleasantly surprised by the quality of the noise reduction at the camera's highest ISO 12,800 sensitivity--"pleasantly surprised" doesn't mean it's more than an emergency mode, as with its competitors, though.
Furthermore, though it lacks a neutral color setting, the standard Creative Style parameters didn't induce too much of a color shift, and it delivered very good color accuracy numbers in CNET Labs tests--better than most of its low-end dSLR siblings. Nor does the camera seem to oversharpen, either. But none of my photos really wowed me, and I shot about 500. Most had a very point-and-shoot quality to them--not the oversharpened look, but the details-never-really-resolved appearance, even with expensive lenses--and there's an overly cool white balance in daylight.
For point-and-shoot upgraders who want better video, the A55V gets a qualified recommendation; the quality is pretty solid, it can autofocus well enough for casual use (albeit loudly--you'll definitely want to use a hot-shoe microphone), and the interchangeable-lens system means you'll be able to put on a long zoom lens for shooting your kids' sports or school plays. Much has been made about the SLTs automatically shutting down for overheating--and it happened to me on a particularly hot day--but keep in mind that no dSLR or ILC can shoot for long stretches without needing a break (here's Sony's table of estimated durations). They're not camcorders. Using the image stabilization really cuts into the recording time, though.
Creative shooters who are looking for a cheap entry into dSLR video should look elsewhere. The video is softer than I'd like, with some surprising moiré in spots, there are practically no manual controls, and unhacked AVCHD cameras don't support any progressive 1080 modes (though it looks like the hacking has begun). There's an aperture-priority movie capture mode, but it only works with manual focus, and it locks the aperture wide open. This is likely to keep the A-mount lens' loud aperture activation from registering on the audio track.
As for speed, the A55V performs reasonably well: it's a tad slower overall than competing dSLRs, but quite a bit better than its fastest mirrorless competitors. It powers on and shoots in about half a second, and in good light can focus and shoot in an excellent 0.3 second; in dim light that rises to a relatively slow 0.7 second. Typical JPEG shot-to-shot time runs around 0.6 seconds--raw is a hair slower--which rises to 1.2 seconds with flash enabled. The latter is a bit slow compared with dSLRs. For burst shooting, however, it not only leads its class, but it's pretty fast for any class. The standard burst mode clocks at about 6.1 frames per second; its Continuous Advance Priority AE mode is rated to hit about 10 frames per second, but you forgo the ability to control shutter speed. Keep in mind that a fast (30MB/sec or better) SD card will make a big difference in your burst performance experience. Finally, the battery life is spectacularly unimpressive.
I give the camera high marks for general photographic usability. The EVF is probably the best I've ever used. But while I love EVFs for shooting video, and that's one of the things that give the SLT models a decided advantage over the A580, a dSLR which otherwise has a similar set of video capabilities, there are still trade-offs between EVFs and optical viewfinders when it comes to burst shooting. Even the best EVF can't refresh quickly enough to allow for panning or easily following the subject. And the drop-down articulated LCD, like the one on the Nikon D5000, comes in very handy.
|Canon EOS Rebel T2i||Panasonic Lumix DMC-GH2||Sony Alpha SLT-A33||Sony Alpha SLT-A55||Sony Alpha DSLR-A580|
|Sensor (effective resolution)||18-megapixel CMOS||16.1-megapixel Live MOS||14.2-megapixel Exmor HD CMOS||16.2-megapixel Exmor HD CMOS||16.2-megapixel Exmor HD CMOS|
|22.3 x 14.9mm||17.3 x 13.0mm||23.4mm x 15.6mm||23.5mm x 15.6mm||23.5mm x 15.6mm|
|Sensitivity range||ISO 100 - ISO 6,400/ 12,800 (expanded)||ISO 160 - ISO 12,800||ISO 100 - ISO 1,600/12,800 (expanded)||ISO 100 - ISO 1,600/12,800 (expanded)||ISO 100 - ISO 12,800/25,600 (expanded)|
|Continuous shooting||3.7 fps |
34 JPEG/ 6 raw
|5.0 fps |
unlimited JPEG/ 7 raw
|6 fps (7fps with auto exposure) |
16 raw/7 JPEG
|6 fps (10fps with auto exposure) |
20 raw/35 JPEG
|5 fps (7fps with auto exposure)|
22 raw/45 JPEG
n/a/1.5 million dots
0.46 inches/1.4 million dots
0.46 inches/1.2 million dots
|Autofocus||9-point phase-detection AF center cross-type||23-area contrast AF||15-pt phase-detection AF |
|15-pt phase-detection AF |
|15-pt phase-detection AF|
|Shutter speed||1/4000 to 30 secs; bulb; 1/200 x-sync||1/4000 to 60 secs; bulb up to 2 minutes; 1/160 x-sync||1/4000 to 30 secs; bulb; 1/160 x-sync||1/4000 to 30 secs; bulb; 1/160 x-sync||1/4000 to 30 secs; bulb; 1/160 x-sync|
|Metering||63 zone||144 zone||1200 zone||1200 zone||1200 zone|
|Image stabilization||Optical||Optical||Sensor shift||Sensor shift||Sensor shift|
|Video||H.264 QuickTime MOV 1080/30p/25p/24p n/a; 720/60p/50p n/a||AVCHD 1080/60i/50i/24p (60p sensor output) @ 24, 17, 13Mbps; 720/60p @ 17, 13Mbps |
QuickTime MOV Motion JPEG
|AVCHD 1080/60i @ 17Mbps; H.264 MPEG-4 1440x1080/30p @ 12Mbps||AVCHD 1080/60i @ 17Mbps; H.264 MPEG-4 1440x1080/30p @ 12Mbps||AVCHD 1080/60i @ 17Mbps; H.264 MPEG-4 1440x1080/30p @ 12Mbps|
|Audio||Mono; mic input||Stereo, mic input||Stereo; mic input||Stereo; mic input||Stereo; mic input|
|LCD size||3 inches fixed |
1.04 million dots
|3 inches articulated |
|3 inches articulated |
|3 inches articulated |
|3 inches articulated|
|Battery life (CIPA rating)||470 shots||340 shots||270 shots||330 shots||1050 shots|
|Dimensions (inches, WHD)||5.1 x 3.8 x 3.0||4.9 x 3.5 x 3.0||4.9 x 3.6 x 3.3||4.9 x 3.6 x 3.3||5.4 x 4.1 x 3.3|
|Body operating weight (ounces)||18.6||15.2 (est)||17.5 (est)||17.8||24 (est)|
|Mfr. Price||n/a||$899.95 (body only)||$649.99 (body only)||$749.99 (body only)||$799.99 (body only)|
|$899.99 (with 18-55mm f3.5-5.6 lens)||$999.95 (with 14-42mm lens)||$749.99 (with 18-55mm lens)||$849.99 (with 18-55mm lens)||$899.99 (with 18-55mm lens)|
|n/a||$1499.95 (with 14-140mm lens)||n/a||n/a||n/a|
|Ship date||March 2010||December 2010||August 2010||September 2010||November 2010|
The camera functions very much like Sony's standard dSLRs, which is a big plus over the NEX's paradoxically dumbed-down yet awkwardly arranged interface. The relatively sparse mode dial contains the usual PASM, auto, flash off, and scene modes, as well as the new Auto+, a late-to-the-party automatic scene selection mode; 10fps Continuous Advance Priority AE mode; and Sony's Sweep Panorama mode. On the back, a Fn button pulls up an interactive display where you can set drive, flash, autofocus mode and area, face detection and smile shutter, ISO sensitivity, metering, flash compensation, DRO/Auto HDR, and Creative Style. The AF button initiates autofocus.
The camera also includes Sony's usual assortment of multishot modes like Auto HDR (increased to six shots for a possible 6EV increase in tonal range), Handheld Twilight, Sweep Panorama, and Sweep 3D. The geotagging on the A55V works seamlessly; as far as I could tell it didn't add any performance overhead and accurately tagged the photos. As with most GPS-supporting cameras, though, getting a lock here in NYC takes some doing.
My only real problem with the features is how scattered they are around the interface; I know that technologically, the Continuous Advance Priority AE is a different animal from standard burst mode, but as a user I expect to find it living under the drive modes, not as a separate mode on the dial. And while I know that Auto HDR doesn't work with raw+JPEG, the camera shouldn't just leave me staring at the grayed-out option for it, forcing me to not only remember why it's grayed out, but then make me jump through the menus to change the quality. Moment lost. (For a full accounting of the A55V's features and operation, download the PDF manual.)
I can't help but think that a camera like the A55V is what people are really looking for when they gravitate toward megazooms; to me, that's where it fits in the photographic hierarchy. Most snapshooters looking to step up want something faster and with better overall photo quality than their current cameras, but usually want it for a lot less than the A55V costs. If the A33 delivers comparable image quality (admittedly a big "if") and you don't want the GPS, then it's definitely a better deal, albeit still on the expensive side. However, if you're willing to spend the bucks--or wait until the price inevitably drops by about $100 off list--the A55V should deliver on the performance and photo quality an upgrader is looking for.