More than megapixels - what really counts in a smartphone camera

Just about every new phone that launches has ads that focus on photography. While most refrain from saying it in as many words, manufacturers manage to coyly suggest that their phone's camera is better than even a DSLR, pointing, on most occasions, to the high megapixel count. Nokia holds the crown for the smartphone with the highest-megapixel count with the 41-megapixel 808 PureView and the Lumia 1020, though rumours now point to a 50-megapixel camera in Oppo's next phone.

In real world testing though, only a few phones have managed to come close to the quality and control that you get with even a mid-range point-and-shoot camera - forget about being better than a DSLR. Why is that?

When Nokia first came up with the PureView technology used in the 808, its announcement of the 41-megapixel camera toting phone made no sense. However, thanks to the camera companies themselves, the term megapixel had become a kind of shorthand for image quality. When point-and-shoot digital cameras were gaining in popularity, Nikon, Canon and other manufacturers got into a race to fit in higher-resolution sensors into their compact cameras, and marketed the term widely. This has parallels with the GHz wars that played out between Intel and AMD during the heydays of the PC industry.

Today though, this tactic has come to haunt the camera manufacturers (much like what Intel and AMD suffered), and people in both Canon and Nikon are the first to point out that a 5-megapixel resolution is high enough to take a clear print-out on an A4 sized page.

That, incidentally, is the standard resolution for images you will get on the Nokia Lumia 1020 PureView. This is because Nokia uses a technology called oversampling, which uses software to treat the individual pixels as a single unit, and essentially creates artificially big pixels on the image sensor.

The image sensor - essentially a plate where the light falls through the lens, where the picture is formed - is probably the most important factor in actually determining quality. NDTV Gadgets spoke to Abhishek Singh, a Technical Officer at Nikon India, who shared his thoughts on the subject.

"The current thinking about megapixels is highly misleading," Singh says. "As a measure of resolution, it just tells you how big the image you're taking is. How much can you crop, without pixelation. That's when the original image is too small and you zoom, so it starts to look blocky. But with a 16-megapixel image, even if I crop to 50% of the image, it won't look pixelated when printed."

In fact, the 8-megapixel iPhone 4S camera was used by the Time magazine in November 2012 for its cover photo. The only time you would actually use a full 41-megapixel image is if you wanted to print the image on a billboard, which is why Nokia over-samples the pictures and produces clearer 5-megapixel.

The real reason that a Lumia 1020 produces better pictures than it's contemporaries is twofold. One of the reasons is that it simply gives the user a lot more control over individual settings like aperture. But the first - and most important reason - is that it has a much bigger sensor than any other smartphone (other than the 808 PureView).

"The image is formed when the light forms on the sensor," Singh explains. "If the sensor size is big then the image will be more detailed, even when you crop into smaller parts of the image and enlarge them."

So where do the megapixels fit into this? According to Singh, the problem comes when you try and pack too many pixels into a small sensor.

"It's like a room. A room that has space for 10 people, you put ten people there and everyone is comfortable. But when you squeeze 20 in there, then it becomes uncomfortable, and when you reach 40 people, no one can breathe," Singh says. "When you pack the individual pixels too tightly on a sensor, the image quality goes down." That is why the images on many budget phones look blurry as they struggle to balance 'advertising friendly' megapixel counts, while still keeping the sensor small enough to fit on the thinner than ever devices.

According to Singh, finding out about the sensor size of a device - instead of the megapixel count - is a quick way of knowing how clear a picture will be, whether you are looking to buy a smartphone, or a compact digital camera. He says that another detail that casual buyers need to learn more about is the ISO or sensitivity of a camera. "A high ISO setting means that you will be able to take a picture in poor lighting without difficulty, but what's happening is that your camera (or phone) is electrically stimulating the sensor to brighten the image. So this can introduce graininess into the image as well."

With a growing trend towards low-light photography and a popular shift away from flash photography, Singh says buyers should also look at the lenses they are getting. Aperture, or the size of the lens opening through which light falls on the sensor, is very important in these scenarios, he says. He adds, "an aperture of f2.2 or f1.8 is becoming more common even in the smaller compact cameras, because of low-light photography." So when a phone's ad promises better pictures in low-light conditions? That has nothing to do with how many megapixels are mentioned in the ad.

Camera manufacturers deserve their share of blame for making people equate megapixels with quality, but it's a figure that phone makers picked up and ran with because it is an easy competition. The fact is that if you want a phone that is super slim and super light and still has a battery life that will last a full day and more - then some compromise has to be made, and that is often done by making a smaller sensor, and making compromises on the lens. If an 8-megapixel camera is good enough for Time magazine's cover, then maybe it's time for customers who'll just be sharing pictures on Facebook to think about what they want from a smartphone camera - and the answer is almost never more megapixels.

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Google Glass review: Uneasy first steps

Shaped like a lopsided headband, Google Glass is an unassuming piece of technology when you're holding it in your hands. You feel as if you can almost break it, testing its flexibility. Putting it on, though, is another story.

Once you do, this Internet-connected eyewear takes on a life of its own. You become "The Person Wearing Google Glass" and all the assumptions that brings with it -about your wealth, boorishness or curiosity. Such is the fate of early adopters of new technologies, whether it's the Sony Walkman, the first iPod with its conspicuous white earbuds, or the Segway scooter. Google calls the people who wear Glass "explorers," because the device is not yet available to the general public.

With its $1,500 price tag, the device is far from having mass appeal. At the South By Southwest Interactive tech jamboree in Austin this week, I counted fewer than a dozen people wearing it, including technology blogger Robert Scoble, who isn't shy about posting pictures of himself in the shower, red-faced, water running, wearing the device.

Google, like most successful technology companies, dreamers and inventors, likes to take a long view on things. It calls some of its most outlandish projects "moonshots." Besides Glass, these include its driverless car, balloons that deliver Internet service to remote parts of the world and contact lenses that monitor glucose levels in diabetics.

There's an inherent risk in moonshots, however: What if you never reach the moon? Ten years from now, we may look back at Google Glass as one of those short-lived bridges that takes us from one technological breakthrough to the next, just as pagers, MP3 players and personal digital assistants paved the way for the era of the smartphone. Fitness bands, too, may fit into this category.

In its current, early version, Google Glass feels bulky on my face and when I look in the mirror I see a futuristic telemarketer looking back at me. Wearing it on the subway while a homeless man shuffled through the car begging for change made me feel as if I was sporting a diamond tiara. I sank lower in my seat as he passed. If Google is aiming for mass appeal, the next versions of Glass have to be much smaller and less conspicuous.

Though no one knows for sure where wearable devices will lead us, Rodrigo Martinez, life sciences chief strategist at the Silicon Valley design firm IDEO, has some ideas. "The reason we are talking about wearables is because we are not at implantables yet," he says. "(But) I'm ready. Others are ready."

Nevermind implants, I'm not sure I'm even ready for Google Glass.

Specs in place for the first time, I walked out of Google's Manhattan showroom on a recent Friday afternoon with a sense of unease. A wave of questions washed over me. Why is everyone looking at me? Should I be looking at them? Should I have chosen the orange Glass instead of charcoal?

Ideally, Google Glass lets you do many of the things we now do with our smartphones, such as taking photos, reading news headlines or talking to our mothers on Sunday evenings - hands-free. But it comes with a bit of baggage.

Glass feels heavier when I'm out in public or in a group where I'm the only person wearing it. If I think about it long enough my face starts burning from embarrassment. The device has been described to me as "the scarlet letter of technology" by a friend. The most frequent response I get from my husband when I try to slip Glass on in his presence is "please take that off." This is the same husband who encouraged me to buy a sweater covered in googly-eyed cats.

Instead of looking at the world through a new lens on a crowded rush-hour sidewalk. I felt as if the whole world was looking at me. That's no small feat in New York, where even celebrities are afforded a sense of privacy and where making eye contact with strangers can amount to an entire conversation.

But that's just one side of wearing Google Glass.

The other side is exhilarating. Glass is getting some bad press lately. Some bars and coffee shops in Silicon Valley and Seattle have banned Google Glass, for example, and federal authorities in Ohio interrogated a man earlier this year after he was suspected of recording a movie with the device. Last month, Google put out a Glass etiquette guide that includes the appeal "don't be creepy or rude."

But the truth is that it's a groundbreaking device, even if it doesn't take off, even if it evolves into something completely different, even if we laugh at it 10 years from now while driving our flying cars in the skies of Manhattan.

I strolled around for a few hours with the cyborg glasses, happily snapping photos. With a mere wink, I captured snowy Lower Manhattan streetscapes and my reflection in the grimy subway-car windows.

There were some whispers. ("Did you see? Google Glass!") There were some comments as I squeezed into the subway with my fellow commuters -comparisons to the Segway scooter, and a warning that it will prove to be a huge battery drainer if I use my iPhone to connect Glass to the Internet.

For more human interaction, I walked into a small macaroon shop to buy a friend some birthday sweets. Alone but for the store clerks, I fumbled to take them off, find a place to put them on the small counter and get my wallet out of my bag.

"Sorry. You're the first people I'm interacting with wearing these. I don't mean to be a jerk," I told the man and woman at the counter. I took off Glass for the same reason that I take out my earbuds when I am talking to people. I don't want to appear like I am not paying attention to them.

It was fine, though. The woman thought Glass was cool. The man, he might not have, but he didn't say anything.

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Asus Chromebox review: Great streaming device

Devices that let you watch Netflix and other streaming video services on a big TV screen are popular, but there are limits to what you can watch.

NBC, for instance, didn't make its Olympics apps compatible with Roku, Apple TV and Google's Chromecast. With HBO Go, Comcast subscribers can use Apple TV but not Roku, while it's the other way around for Charter's customers. And with all of these devices, you need an $8-a-month Hulu subscription to watch what you can get for free using desktop computers.

The Internet is the Internet. It shouldn't matter what gadget you're using. But content providers worry that if they make the video streaming experience too much like regular TV, they'll discourage people from watching old-fashioned commercial and pay TV.

So I'm pleased to find a legal way around these restrictions with a new device called the Chromebox.

AsusTek Computer Inc. will start selling it March 28 at a starting price of $179. A version with a faster processor and support for ultra-high-definition video, also known as 4K, will be available in April for $369. That model includes a wireless keyboard and mouse; otherwise, the package is sold separately for $50.

To call the Chromebox a streaming device does it injustice. It's a full-powered desktop computer running Google's Chrome OS system. I'll get into the pros and cons of that later.

You can connect the Chromebox to a standard monitor just like any other desktop. Like other newer desktops, the Chromebox also has an HDMI port to connect to high-definition TVs. That makes it tempting to turn the Chromebox into a streaming device.

With most streaming devices, you need apps for individual services such as Netflix and HBO Go. If there's no app for that service, you can't watch it on the big screen for the most part. That's one of the big shortcomings with Google's Chromecast streaming device. Even though it's just $35, the list of services it supports is paltry.

By contrast, Chromebox works just like any other computer. As long as you can watch something in a Web browser, you can watch it on the big screen.

You can technically do that with any desktop computer if it has an HDMI port or if you get an adapter. Mac computers also have a feature called AirPlay to mirror the display through an Apple TV and your Wi-Fi network.

But those computers typically cost hundreds or even thousands of dollars. The Chromebox is just $80 more than a Roku 3 or an Apple TV, and it lets you watch -and do- much more.

I've managed to use the Chromebox to watch plenty of free Hulu offerings, replays of Olympics figure skating and some shows from ABC Family, a channel otherwise unavailable on streaming devices. Video is sometimes jerky and the audio sometimes out of sync, but that's something I get on other devices, too.

As I mentioned earlier, Chromebox is much more than a streaming device. Because it runs Google's Chrome OS, it comes with a Google's Chrome Web browser and numerous apps for Google services, including Gmail, Google Maps, YouTube and Hangouts chats. You can get apps for non-Google services, too, but not as many as you'd find for Windows and Mac computers.

Chrome OS is ideal for those who use a lot of Google services or can otherwise get what they need over a Web browser. That includes research for homework, checking Facebook and using Web-based email.

If you need professional apps such as Adobe's Photoshop or Microsoft's Office, look elsewhere. The tools available with Chrome OS are adequate for basic functions, but they aren't robust.

Another shortcoming of Chrome OS is its need for a constant Internet connection. Many apps don't work well or at all without that. That's more of a problem with Chrome OS laptops meant for use outside the home. You should never need to separate your Chromebox from the Internet.

Chromebox also has a new Chrome OS feature that lets you create supervised log-ins for your kids. You can choose to block certain sites or permit surfing of only pre-approved sites. You can also see a list of what your kid tried to visit.

Unlike parental control software from outside parties, Chrome OS doesn't try to impose a default list of approved or banned sites. It requires more work to configure, but it lets parents decide what's appropriate.

Chromebox works nicely as a secondary computer that family members share.

Besides the dual display ports, Chromebox has four USB 3.0 ports for printers and other peripherals, a slot for camera memory cards and an Ethernet port for wired Internet connections. It also has Wi-Fi, but not the newer, faster type known as 802.11ac.

My one complaint: You'll have to decide whether you want to use the Chromebox as a general-purpose computer or as a streaming device.

I recommend getting the wireless keyboard and mouse for streaming. Otherwise, the keyboard and mouse would be physically attached to the Chromebox, which sits closer to the TV than to you.

But that setup doesn't work well for general computing. I find text too small to read on a 42-inch (106-centimeter) TV that's 8 or 10 feet away. For general computing, you'll want a smaller screen and you'll want to be closer to it. But then it's no different from watching streaming video on a regular computer.

Of course, the Chromebox is cheap enough that you can buy two. But if you have to choose, consider this: There are plenty of other desktops for general computing, but few affordable enough to use just for streaming.

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