Report David Pogue | October 11, 2010
When it made up the term "SLR,'' the technology terminology industry was not operating at its peak creative powers. 
An  SLR is one of those big, black, professional-style cameras. They do  things that make pocket cameras look like pretenders: They can blur the  background, take lower-light shots without a flash and shoot with no  shutter lag (the delay after you press the shutter button). 
And thanks to enormous light sensors and lenses, the photos just look fantastic. 
But ouch — that name. Even if you know what SLR stands for ("single-lens reflex''), you have no idea what it means. 
   
"Single lens'' is misleading, because the whole point of these cameras is that you can attach dozens of different lenses. 
And to most people, "reflex'' refers only to wincing when they see the price. 
  Kidding  aside, historically, there was a point to the term "single-lens  reflex''. It describes the mirrors and prisms inside that bend the light  from the lens to your eye. 
Recently, a new generation of mirrorless cameras have hit the market. 
They  look and work like SLRs — interchangeable lenses, no shutter lag and so  on — but they're smaller and they capture high-definition video. (Since  they're not technically SLRs anymore, Popular Photography magazine  proposes the term ILC for them, for "interchangeable-lens compacts.''  Let's run with it). 
Sony's new Alpha A55 camera, available in  October ($850 with 3X zoom lens), is an SLR — sorry, an ILC — that  changes a bunch of games at once. 
It accepts any of Sony's  existing 33 Alpha lenses, but its radically different guts give it  talents no other camera has had before. 
Explaining the A55's  innovations will require a paragraph or two of technical slogging, but  you'll feel rosy and smart when it's over. 
In a typical SLR,  light from the lens hits a mirror, which bounces light up to your eye  and onto a focusing sensor. The blessing: you see what the lens sees.  The curse: when you take the actual photo, the mirror has to flip out of  the way so that the light falls on the main image sensor (the "film'').  For that fraction of a second, the camera can't focus. If someone or  something is hurtling toward you, a typical SLR may have trouble keeping  rapid-fire shots in focus. 
That's also why most SLRs can't  change focus when you're shooting video. If you start filming on  something close up, and then pan to something across the room, the video  goes out of focus. 
Still with me? 
Sony's A55 camera  adopts a new spin on a decades-old photographic idea: The mirror is  translucent. It splits light between the focusing sensor and the image  sensor — all the time. The mirror never has to flip up to take a  picture, so the autofocus never goes blind when you take a shot. 
The camera can shoot an incredible 10 shots a second, refocusing all the way. Sony says no other camera can do that. 
The  camera also shoots beautiful, high-definition video, and it can change  focus as you pan the camera, gorgeously and cinematically. 
Very few SLRs, or even ILCs, can do that trick — refocusing while filming. 
But  the Sony doesn't just change focus in video. It changes focus fast.  According to Sony, the A55 is the first camera — or camcorder, for that  matter — to use what's called phase-detection focusing for video. (Other  cameras, and all camcorders, use a slower system called contrast  detection.) 
That's only possible because, in this camera, the autofocus sensor can see the scene all the time. 
Now, to pull off this unusual design, something had to go — in the A55's case, the optical viewfinder. 
   
When  you hold the A55 to your eye, you're basically looking at a tiny TV  screen in the eyepiece, rather then peering out through the glass of the  lens. In other words, it's an electronic viewfinder. 
Photographers usually pooh-pooh electronic viewfinders, because no screen is as sharp as real life. 
But Sony's viewfinder is extremely big, bright and sharp (how does 1.4 million pixels strike you?). 
   
And having a screen in the eyepiece gives you all kinds of advantages you don't get when you're just looking through glass. 
For  example, you can see exactly what effect your settings will have before  you take the shot (white balance, exposure, focus, and so on). 
You  can summon digital overlays in the viewfinder, including a horizon  level. You can magnify the scene up to 15 times for precise manual  focusing. 
You can play back your photos right in the viewfinder —  a rare, surprisingly handy feature, especially when you're  experimenting with settings or reviewing your photos in bright sunlight  (which washes out the screen somewhat). 
You can shoot video with  the camera to your face, too, a more stable way of holding the camera.  (Most SLRs require you to look at the screen on the back to shoot  video.) 
The best part is that these gee-whiz features are part of a generally terrific camera. 
The  A55 has Sony's Sweep Panorama mode, where you swing your arm in an arc  as the camera snaps away — and then, two seconds later, the camera  displays an automatically assembled, stunning 270-degree panoramic  photo. 
The quality is fantastic, although it's auto-mode. 
The  A55 also creates high-dynamic range photos automatically — a neat trick  by which it creates brighter brights and darker darks by superimposing  three photos with different exposures. 
There's a built-in stereo microphone for use with your video, plus a mike jack. 
The  button placement is excellent — especially the dedicated Video Record  button (no switching modes when filmic inspiration strikes). 
The  tilting, rotating, flip-out screen lets you shoot over your head, at  knee level or even self-portraits. You can also fold the screen flush  against the camera (with either screen in, for protection, or screen  out). 
I was so confident in the A55's ability not to muff photo  ops that I did a risky thing: I used it as the sole recording device for  my son's one and only sixth birthday party. 
Happy ending — the ratio of winner shots to losers was amazingly high. 
Even the low-light candle-blowing moment looks fantastic in video, like Scorsese shot it. 
   
Now, there are a few flies in the ointment. 
That  10-frames-a-second mode requires a lot of light; indoors, these  superburst-mode photos are sometimes too dim, and you can't adjust the  aperture in this mode. 
The camera is small and light compared  with true SLRs, but it's still much bulkier than, for example, Sony's  own minuscule NEX-5 (the smallest of this type in the world, although  you give up a lot of features — like a flash, a mode dial and a wide  choice of lenses). 
There are two playback modes, one each for  stills and videos, and it's annoying to have to switch between them.  Battery life is about 350 shots a charge, which could be better. 
And  some of the fancy modes (like high dynamic range) require a lot of  processing after each shot, during which time you can't use the camera. 
Still,  the A55 takes pictures and videos as well as anything in its price  range — and, in some cases, better than far more expensive equipment. (A  sibling camera, the A33, is available now for $100 less. 
It  gives you seven frames a second instead of 10, and 14 megapixels instead  of 16; it also does away with the GPS chip that tags each photo with  your location.) 
Even more exciting, it's thrilling to see Sony  finding its mojo again, introducing radical new design ideas that, in  this case, really advance the state of the art. 
In other words, maybe the right term for the A55 is neither SLR nor ILC. Maybe it's really an ESF (exciting step forward). 
  
The New York Times
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http://www.thejakartaglobe.com/lifeandtimes/sony-makes-giant-leap-with-a55/400693