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johnnymk
08-20-2009, 05:29 AM
http://www.nytimes.com/2009/08/20/technology/personaltech/20pogue.html?_r=1&th=&emc=th&pagewanted=print


For years now, the world’s camera companies have been taking the public for a ride. They’ve taught us to believe that what makes one camera better than another is the number of megapixels it has — when, in fact, the number of tiny colored dots making up a photo has very little to do with its color, clarity or even detail.

Slowly, though, the truth is getting out. Recently (at long last), camera companies have begun diverting their research efforts from “how to get more megapixels” to “how to get better photos.” They’re working on things that really do matter in a consumer camera, like sensor size, stabilization — and fixing low-light photography.

In that last category, please welcome the Fujifilm FinePix F200EXR and the Sony DSC-WX1 ($320 and $350, respectively, before discounting). Each comes accompanied by breathless marketing hype (“a breakthrough in low-light photography: stunning detail and low noise in scenes with no more than candlelight” says Sony) — but each, in its way, truly is an important step forward.

That’s because, in the world of pocket cameras like these, “low light” basically means “nightmare.” Once the sun goes down, the compromises begin.

You can put the camera on a tripod. That way, even though the shutter stays open a long time (to soak up more light), the camera doesn’t move, so blur isn’t a problem.

O.K., so you’re now supposed to lug around a tripod to go with your microscopic camera? Surrrrre you are.

Alternatively, on most cameras, you can crank up the ISO (light-sensitivity) setting. Now the camera soaks in more light, but at a terrible price: the teeming multicolored random grainy speckles known as “noise.” Or, worse, hopelessly “soft” smeared images that result from a camera’s overzealous antinoise circuitry.

Of course, you can always use the flash. Unfortunately, a flash photo isn’t what you saw with your own eyes. It’s something else, an image that usually features nuclear-bleached faces and cave-black backgrounds. And it doesn’t work farther than about 10 feet away.

(Those big heavy black S.L.R. cameras do much better in low light without the flash, simply because they contain gigantic sensors.)

Fujifilm and Sony have each tackled this problem exactly the right way, the hard way: by redesigning the sensor itself, the tiny rectangular chip at the heart of every digital camera.

For years, Fuji has been bragging about the unconventional layout of its sensors. On this chip, the tiny individual pixel sensors (called photosites) aren’t square; they’re hexagonal, arrayed in a honeycomb. That’s supposed to expose more sensor surface to the incoming light.

The new sensor in the F200EXR, though, goes a step further. In what’s called EXR mode, it can merge two adjacent photosites, in effect doubling the light collected at that spot on the sensor. Of course, this trick also halves the megapixels — you get 6-megapixel shots instead of 12. But amazingly enough, in low light, those 6-megapixel shots are actually sharper and more detailed than the 12-megapixel shots from the same camera.

Sony gave the sensor a makeover, too. According to Sony, a sensor is actually a sandwich of layers: tiny lenses on top, then color filters, then some wiring, then the actual light detectors on the bottom. Sony says that in its new Exmor R sensor, the circuitry layer has been moved to the bottom, so that less light is lost en route through the stack.

Does any of this make any difference?

It sure does. I spent three successive evenings shooting the same twilight and nighttime scenes with the Sony, the Fuji and my own Canon PowerShot SD880, a terrific 2008 camera with no special low-light features.

Now, I am a rabid fan of Canon pocket cameras, having found them to be the best on the market year after year. But in almost every one of my after-sundown tests, the Canon photo was too blurry to be useful. The Fuji and Sony shots were sometimes grainy (an S.L.R. would have done better) but were always sharper, and managed to capture something in anything shy of total blackness. (A slide show of example shots accompanies this article at nytimes.com/personaltech.)

It’s truly amazing; there hasn’t been an advance in small cameras this important since image stabilization came along.

In most cases, the Sony did even better than the Fuji. Some of its shots — like those taken with only a single candle as illumination — were nothing short of miraculous.

The Sony performs two other stunts that will make your jaw drop. From its much larger, zoomier cousin, the HX1, the WX1 inherits Sweep Panorama mode. As you whip the camera in an arc around your body, it quietly snaps 10 consecutive photos, figures out how to connect them, and spits out a finished 270-degree panorama. Talk about wide-angle!

There are some limits to this magic: the resulting photo is “only” seven megapixels for the whole image (the camera ordinarily shoots 10-megapixel images); the exposure is fixed at the far left end of the sweep; and people or things that move during your sweep may appear twice, squished or chopped off. But still, how great to show the majesty of the Grand Canyon or some other vista with a single press of the shutter button.

The Sony’s other great trick is capturing 10 images in a one-second burst, a capture speed that puts most other pocket cams to shame. Unfortunately, the camera locks up for 18 seconds afterward, as it processes all those shots.

Even so, the Sony WX1 is a standout camera. For a machine that’s so simple to use, it’s filled with delights. They include superfast start-up, fast focusing, a 5X-zoom lens and high-definition video capture. You can change focus while filming, and even zoom in and out — a rarity in still cameras, probably because the noise of the zooming motor is deafening on the soundtrack. But sometimes, a noisy zoom is better than no zoom at all.

Both cameras can choose the correct mode (close-up, twilight, portrait, landscape and so on) automatically. Both have only a screen — no eyepiece viewfinder — which makes them tricky to use in bright sunlight. Then again, both cameras are tiny enough to rattle around in a shirt pocket. Both offer excellent face recognition, meaning that portraits are almost always focused and properly exposed. Neither offers manual focusing.

There are drawbacks. The Sony requires one of those goofy Memory Stick Duo memory cards (why can’t Sony just use SD cards like the rest of the world?) and the Fuji camera has poor battery life, slow burst mode and few manual controls. The Fuji’s other heavily promoted feature, Dynamic Range mode, can recover detail in portions of the image that would otherwise be “blown out” (white patches). Unfortunately, you can see the difference in very few shots.

So yes, the Sony WX1 pretty much mops the floor with the Fuji. Of course, this is by no means a fair comparison; the Fuji is six months old at this point, and the Sony isn’t even on the market yet. (A sister camera, the Sony TX1, is thinner, with a touch screen and less zooming power; it’s available now.) A new Fuji, the F70EXR, comes out next month, with the same special sensor, an amazing 10X zoom and other goodies. As soon as it arrives I’ll review it in my Personal Tech e-mail column (sign up at nytimes.com/email).

So does this settle the “What camera should I buy?” question? Unfortunately, not quite. You’ve still got some agonizing to do. The Sony WX1 is nearly irresistible for its low-light abilities, HD video, sweep panorama and burst mode. Still, in good light, a Canon PowerShot still offers better color and sharpness.

In the meantime, it’s official: another chronic disappointment of small cameras has now fallen away. It’s a pleasure to announce that those clever camera engineers, long obsessed by megapixels, have finally come to their sensors.

Thesifer
08-20-2009, 01:49 PM
Megapixels have always only mattered if you're actually blowing your pictures up.

InfiniteNothing
08-20-2009, 02:05 PM
Megapixels have always only mattered if you're actually blowing your pictures up.
And even then they aren't that important. If you are always about the same as your 8 closest neighbors you've effectively ninethed your resolution.

Thesifer
08-20-2009, 06:16 PM
And even then they aren't that important. If you are always about the same as your 8 closest neighbors you've effectively ninethed your resolution.


After a certain point they aren't that important, but it all depends on size of the photo you want to achieve. And overall picture clarity. Picture taken with a 4mp camera will look pretty shotty if you want it to be a large family photograph above your fireplace.

ArkiStan
08-20-2009, 06:36 PM
I wouldn't go so far as to say resolution isn't important. It just shouldn't be the highest priority when it comes to choosing a camera.

zippyjuan
08-20-2009, 06:40 PM
Megapixels is still a pretty strong marketing tool. One of the first questions anybody asks about a camera is "how many megapixels is it?" but today, that number does not really mean much. The next thing is zoom range. But technoligically, the action today is more on low light performance. Most point and shoots do pretty poorly when it starts getting darker. Fuji has been a leader in this field in point and shoot cameras with their own SuperCCD technology and Sony actually makes the sensors for many other brands as well so they have put a lot of research into it (yeah, I hate their memory stick thing too). The cameras they look at in the article are pretty interesting sounding. The Fuji camera the article mentions is supposed to be out later this month- it is still a small point and shoot size but has a 10mp sensor and a 10x zoom range (27- 270mm equivalent) in a compact size (all other 10x zooms are a lot larger) and is said to retail about $300. If you want an all-purpose camera with a wide range in both lighting situations and zoom that you can carry in your pocket, this could be an excellent camera. Fuji used to use the more expensive XD cards (my F31fd does- cost me about $45 for a GB card) but has switched to SD. http://www.dpreview.com/news/0907/09072209fujifilmf70exr.asp

Their aproach to reducing noise:

Pixel Fusion Technology: Technology of Fujifilm changing the colour filter arrangement. Two side-by-side, same-coloured pixels are taken together as a single pixel. The area of imaging elements is doubled, the sensitivity is twice the normal level, and "dark noise" is extremely small. Therefore, it is possible to create a high sensitivity image with little noise, instead of increasing the gain from a single pixel and increasing the noise

Jeffbx
08-21-2009, 09:30 AM
The whole article is summed up with this one sentence:


(Those big heavy black S.L.R. cameras do much better in low light without the flash, simply because they contain gigantic sensors.)

And when you can get a (used) digital SLR for $300 and you want to shoot in low light, then.....

InfiniteNothing
08-21-2009, 09:31 AM
After a certain point they aren't that important, but it all depends on size of the photo you want to achieve. And overall picture clarity. Picture taken with a 4mp camera will look pretty shotty if you want it to be a large family photograph above your fireplace.
4 mp will look just fine as an 8x10. The same picture taken with a 12 mp camera will look shotty if the sensor is too small. At that point, the limiting resolution is your signal to noise ratio

ray
08-22-2009, 08:44 AM
4 mp will look just fine as an 8x10.

Agreed. It is probably being printed at 200ppi instead of 300ppi at that point, but still good quality to the naked eye.

Though this site is old, it gives a sense of how megapixels help with size of prints at 300ppi.

http://www.design215.com/toolbox/megapixels.php

Airencracken
08-22-2009, 08:47 AM
Pixel size matters a lot (the actual size of each individual pixel) and so does sensor size and glass. Pixel binning is an iffy technology. Sigma's foveon sensor is interesting, but they are lower sensitivity than most bayer pattern sensors.

Besides, some of us prefer grain and still shoot film. Heh. :)