What really matters in a digital camera

David Pogue has bought a Canon PowerShot S95 pocket camera and writes that a major feature is its large sensor.

I love the huge light sensor that's inside an SLR. It can take sharp low-light shots without the flash. It can blur the background the way professionals do.

What I've always wanted is a little camera with a big sensor. Is that so hard? Apparently, yes. The problem is covering a rectangular sensor chip with a circle of light from the lens. Bigger sensor? You need a bigger camera. Those are the simple bylaws of physics.

The S95's sensor is 0.59 inches diagonally -- 88 percent more area than most pocket cameras' sensors. What this means:

The little S95, can take amazing, sharp pictures in low light without the flash. The designers have shrewdly dropped the ludicrous quest for more megapixels -- it has 10 megapixels, just right -- in favor of something that really matters, like better photos. So many times I've used it  for pictures at night, indoors, in shadow. Cathedrals, restaurants, parties. No, the results aren't as good as an SLR's -- it still manages to blur a shot, especially in very dark situations when the subject is moving -- but they're light-years better than any other pocket camera can do.

The bottom line is that just counting megapixels won't tell you everything about a camera's performance. Here's a bit more on this, from Digicamhelp:

The size of a camera sensor will have a big impact on the quality of your pictures. The lens gathers light and directs it towards the sensor, and the sensor records the light to create the image.

All things being equal, a larger sensor will receive more light than a smaller one, and produce better images. This is especially important in low light photography.

When light levels are low, a smaller sensor will generate a higher amount of noise, which will decrease the quality of the images. This is why the best low-light setups include a camera with a large sensor (usually a DSLR) and a lens with a large aperture.


In the compact world, most sensors are equivalent in size. Sensor size for compacts is calculated by measuring the sensors diagonally. The most common sizes are 1/2.5 (0.4) and 1/2.3 (0.43) inches. Pretty small by all accounts.

Manufacturers have started including larger sensors in some of their compacts. For instance, Canon’s s90 camera has a 1/1.7 (0.58) niches sensor. This represents a total area 37% larger than most comparable models, and yields much better low light pictures. Compact cameras like the Panasonic LX5 also sport larger sensors.

Something to consider if you're in the market.

Image: Relative sizes of digital camera sensors

Routine maintenance for your PC

Your PC needs some TLC every now and then. You can get a store to do it, for a fee. Staples, hoping to win new customers, will do it for free.

However, you can do it yourself, The New York Times reports. “Tools to do everything that Staples does are built into Windows 7,” said Ben Rudolph, Microsoft’s Windows PC Evangelist. “It’s not that hard to change your own oil.”

Here's the rundown.

It’s important to run antivirus software regularly. Microsoft offers MS Security Essentials, free antivirus software available from Microsoft.com. Mr. Ackerman recommends another free program, AVG Free (free.avg.com).

To avoid leaving any fragments of applications on the drive after you remove a program, use the application’s own removal tool, rather than just putting the program icon in the trash. If you don’t have the tool, do an Internet search for “[program name] removal tool.”

Defragment your hard drive. After extensive use, large programs tend to become “fragmented,” meaning that critical files are scattered across multiple sectors of a drive. It takes the computer extra time to find and assemble all the pieces needed to run the program. Defragmenting the drive will retrieve the files and place them closer together, speeding up the response time when you run the program.

The preinstalled Windows Disk Defragmenter tool, (search for “defragment” under the Start menu in Windows 7, or look for it under Programs>Accessories>System Tools in most older Windows machines) will defragment your hard drive, either manually, or automatically on a schedule you can customize.

Defragmenting a hard drive can take anywhere from a few minutes to a few hours depending on the size of the drive and how cluttered it is.

Most maintenance tools are easily found in Windows 7. Click on the small white flag in the bottom right of the screen to bring up the Action Center. If you haven’t installed antivirus software, you’ll be prompted to find such a program. You’re also given the option to back up your hard drive. 

Reviewing the new MacBook Air

I don't have an iPad, although I can see the day coming. I have a MacBook Pro, which I love and which is too new to replace. When that time comes, it may be that I can have both in the same machine.

Walt Mossberg, The Wall Street Journal's technology guru, has reviewed the new MacBook Air and found:

Some of the nicest, if little discussed, benefits of using an Apple iPad tablet are that it starts instantly, resumes where you left off, and has a long enough battery life that you aren't constantly fretting about running out of juice or looking for a place to plug it in. And it can do a lot of things for which people use laptops.

What if somebody designed an actual laptop that worked this way—you know, a computer with a real keyboard and a larger screen that could run traditional computer software and store more files than an iPad? And what if it was almost as light and portable as an iPad? Well, somebody has, and that somebody is Apple itself.

The new Air, he writes, comes to life almost instantly and yet has tremendous battery life.

In my harsh battery tests, I found the two new Air models almost matched Apple's battery claims, even with all power-saving features turned off, Wi-Fi kept on, the screen on maximum brightness and a continuous loop of music playing. The 11-inch model lasted four hours and 43 minutes, versus Apple's claim of up to five hours. The 13-inch model lasted six hours and 13 minutes, versus Apple's claim of up to seven hours.

It has less storage to make room for its better battery, he notes, a problem for someone needed to store big amounts of video, for example. And other things, like a DVD drive, have to be purchased separately.

"Overall," Mossberg writes, "Apple has done a nice job in making these new MacBook Airs feel more like iPads and iPhones without sacrificing their ability to work like regular computers."

Do you need a PowerMonkey?

I get occasional emails from an outfit I'm fond of -- Extreme Outfitters, your one stop shop for all things tactical. This is the online version of the Army Navy store in my town when I was growing up. It's the place for combat boots, knives, you name it.

This particular email advertised various power supplies, including the PowerMonkey-eXplorer, a portable solar charger for mobile phones, iPods, PDAs and more. I just don't know how I ever did without it. I mean the name alone ...


Here are some details:

From the heart of Africa to the Hardanger Glacier, the powermonkey-eXplorer portable charger has proved to be an invaluable piece of kit, providing essential power in the most remote locations. Incorporating the new solarmonkey solar charger, the powermonkey-eXplorer lets you charge wherever, whenever. 

The heart of Africa! I bet it even works in your cube, if you sit by a window. 

It gives you 96 hours of standby on your mobile, 40 hours on your iPod, 5 hours on your games console, 48 hours on your PDA and 6 hours on MP3/MP4 players. 

More:

Ultra compact, tough, powerful and Made for iPod approved, the powermonkey-eXplorer is water resistant and made from rubberised casing so can take whatever life throws at it, yet it remains the lightest, most versatile portable charger available today.

Seriously, if you go hiking or camping, or you're just on the road and needing some juice, it sounds ideal.

Create your own x-rays

Well,  not quite. But look what happens when you play around with Scotch tape. From Science News:

Forget fancy particle accelerators — a cheaper tool for emitting X-rays is right there in the office supply cabinet. Pulling back Scotch tape emits X-rays, the same high-energy light emanating from airport security scanners and the interiors of galaxy clusters, and scientists now have a better understanding of why.

Scientists have known since the dawn of 3M Scotch tape in the 1930s that pulling the adhesive emits blue light. But to discover that X-rays also fly out was perplexing because X-rays are a hundred thousand times more energetic than the chemical bonds holding the sticky side down.

Here's how it works.

Peeling tape separates positive and negative charges, creating an electric field. The field jump-starts free electrons in the neighborhood, accelerating them fast enough to emit X-ray photons. This bremsstrahlung radiation is like that created in the bellies of particle accelerators as they whip charged particles around near the speed of light.

They say it isn't harmful. Okay, you try it first. At atmospheric pressure, where air molecules bustle, the electrons quickly run into other particles before they can radiate X-rays. But one scientist imagines that soldiers and medical workers in the field could use a hand crank to peel off adhesives and create X-rays. The light is powerful enough to image a human finger.

Should you store your medical record online?

hIt's now possible to store all of you health information online, making it easily accessible anywhere, but only about four percent of people do. Many are afraid of the privacy implications, although these sites use the same technology as banks do to protect your information.

The Wall Street Journal has reviewed three of the most popular sites.

Google Health doesn't have many tools of its own to allow users to evaluate their health. Instead, it focuses on sharing your data with online applications that do such tasks, like the My Diabetes Health Assessment website, which evaluates users' risk of diabetes based on data from their health records.

Microsoft HealthVault, too, has a limited number of self-evaluation tools but connects to a wide variety of helpful services that can extract data from or import data to your profile.

You can accesss WebMD's Health Manager in two main ways: through its public site, WebMD.com, or through the sites of insurance companies and employers that are WebMD customers.

The Journal's assessment:

In the end, we found that each PHR offers a remarkable value for a free application, but none of the three emerged as a clear winner.

Microsoft HealthVault gets high marks for portability, but it has no features for printing. WebMD Health Manager has all of its health evaluation features built in, so you don't have to connect to external applications, but it lacks the ability to export information in some key industry formats. So does Google Health (it says it may add this later), but it does export data to online health applications.

One way to choose among the PHRs is by the applications that link to them. If you want to import data from LifeScan Inc.'s OneTouch glucose monitor into your PHR, for example, currently only HealthVault does that (Google may add this).

On the other hand, if your insurance company (yours or your employer's) is a WebMD customer, you may want to use Health Manager for its easy importing of all the health data your insurance company already has on you.

Also posted on my technology blog, Tell Your Doctor

Reach out and touch some one through Gmail

Does anyone know why we continue to pay hundreds of dollars for phone service?

Consider: Google launched an Internet-based calling service in August. Anyone with a U.S.-based Gmail account, compatible operating system, speakers and a microphone can make and receive phone calls from their inbox, Courtney Banks reports in The Wall Street Journal.

Gmail calling works best with a free Google Voice account, which assigns you a phone number that links to all your other lines – work, home or mobile. It acts like a personal switchboard operator, allowing you to decide which phone will ring when someone dials your Google number. Without Google Voice, you can only place outgoing calls through Gmail. 

"I could choose whether to answer the call on my computer or on my cell phone, and transfer calls between the two by pressing the star key," Ms. Banks writes. "For example, if I was chatting while walking into the house, I could switch the phone to my computer, and switch back if I had to leave. For technical reasons, call transfer only works for incoming calls."

Gmail calling with Google voice is versatile, because it can handle calls to your other phones. For the moment, it's also cheaper for certain types of calls. On Skype, computer-to-computer calls are free. But calling a phone costs 2.3 cents a minute to the U.S. and many other countries, or 2.99 a month for unlimited calls to the U.S. and Canada. On Gmail, all outgoing calls to U.S. and Canadian numbers and all incoming calls are free, through at least the end of the year. Charges for calls to international numbers cost from 2 cents a minute to landlines in much of Europe and Asia, to 99 cents a minute to Cuba.

Did anyone say free?

How cell phones can track illness

I've read about putting sensors on cell phones that would automatically tell a central computer that a biological or chemical terrorist attack was underway. Here's the same idea but in a more personal use.

Epidemiologists know that disease outbreaks change mobility patterns, but until now have been unable to track these patterns in any detail. So says Anmol Madan of the Massachusetts Institute of Technology and colleagues gave cellphones to 70 students in an undergraduate dormitory. The phones came with software that supplied the team with anonymous data on the students' movements, phone calls and text messages. The students also completed daily surveys on their mental and physical health.

A characteristic signature of illness emerged from the data, which was gathered over a 10-week period in early 2009. Students who came down with a fever or full-blown flu tended to move around less and make fewer calls late at night and early in the morning. When Madan trained software to hunt for this signature in the cellphone data, a daily check correctly identified flu victims 90 per cent of the time.

Two possible uses for this have emerged.

• The technique could be used to monitor the health status of individuals who live alone. Madan is developing a smartphone app that will alert a named contact, perhaps a relative or doctor, when a person's communication and movement patterns suggest that they are ill.
• Public health officials could also use the technique to spot emerging outbreaks of illness ahead of conventional detection systems, which today rely on reports from doctors and virus-testing labs. Similar experiments in larger groups and in different communities will have to be done first though.

And you don't have to make an appointment

Folks at the MIT Media Lab are playing around with a prototype of Netra, a system that can identify problems with a person's eyesight using only a smartphone, software, and inexpensive optical add-ons. The system could help people who can't afford or get access to full-service optometry.

Ramesh Raskar, an associate professor at the MIT Media Lab and the leader of the Camera Culture group there, said it dawned on him that the 300 dpi resolution on a smart phone screen made it the rival of expensive, specialized devices.

Raskar said the ubiquity of smartphones is a key part of what makes Netra attractive. While other systems have been proposed to provide optometry where it isn't currently available, those systems were limited by needing expensive equipment, or by being complex enough that they had to be used by an expert.

Similar hardware add-ons could transform smart phones into inexpensive sensor devices that could serve many medical and environmental needs.

Is this the post-PC era?

Here's a look at the media gadgets Americans own.

The technology research firm Gartner expects sales of 19.5 million units in 2010 for tablet devices like the iPad and Kindle and sees this going to a staggering 150 million units by 2013.

iPad sales are through the record roof

People just keep buying this thing, and it's setting records.

iPad sold three million units in the first 80 days after its April release and its current sales rate is about 4.5 million units per quarter, according to Bernstein Research. This sales rate is blowing past the one million units the iPhone sold in its first quarter and the 350,000 units sold in the first year by the DVD player, the most quickly adopted non-phone electronic product.

“The iPad did not seem destined to be a runaway product success straight out of the box,” said Colin McGranahan, retail analyst at Bernstein Research, in a note. “By any account, the iPad is a runaway success of unprecedented proportion.”

The iPad is beating whole categories of electronic devices.

At this current rate, the iPad will pass gaming hardware and the cellular phone to become the 4th biggest consumer electronics category with estimated sales of more than $9 billion in the U.S. next year, according to Bernstein. TVs, smart phones and notebook PCs are the current three largest categories.

This will only grow as Verizon gets into the game.

How do you decide on a Facebook app?

We are strongly influenced by what others do.

Felix Reed-Tsochas of Oxford University's Saïd Business School and Jukka-Pekka Onnela from Harvard University decided to study how users of Facebook use "apps," the little thingies that add to the experience.

The Economist reports:

They pored over (anonymous) data of the entire Facebook population in July and August 2007 (around 50m at the time), and at all but a few of the 2720 apps available for download in the same period. This amounted to a total of some 104m app installations. At that time, a Facebook user's apps were all visible to friends, who were also notified when any new app was downloaded (a practice Facebook has since abandoned). This, along with a display of the total number of installations of each app, were the only ways apps were plugged, permitting the researchers to control for the effects of external advertising. Any effects observed would thus be wholly attributable to social influence, not canny ad men.

Dr Reed-Tsochas and Dr Onnela duly discovered that the social networkers' herd mentality was intact, with popular apps doing best, and the trendiest reaching stratospheric levels. A typical app was installed around 1,000 times, but the highest-ranked notched up an astonishing 12m users. What did come as something of a surprise, though, was that our inner lemming only kicked in once the app had breached a clear threshold rate of about 55 installations a day. Any fewer than that and users seemed oblivious to their friends' preferences. Interestingly, after some serious number crunching, the researchers found that this cannot be put down purely to the network effect, ie, the idea that adopting a certain innovation only makes sense if enough other people have done so. Indeed, this effect appeared less pronounced than might have been expected.

Dr Reed-Tsochas and Dr Onnela suggest that two discrete behavioural patterns emerged. Users appeared to treat any app with more than 55 daily installations differently to those with fewer downloads. Under 55 daily installations, friend behaviour was an instrumental part of the decision to install. Over 55 daily installations, and friend behaviour didn't matter one jot. Virtual lemmings are, it seems, discriminating in ways we still don't quite comprehend. As is, no doubt, the offline troop.

Monkey see, monkey do.

Where am I?

Malls and super box stores are so big these days that we need maps. How about one on your cell phone? The New York Times reports:

A number of start-up companies are charting the interiors of shopping malls, convention centers and airports to keep mobile phone users from getting lost as they walk from the food court to the restroom. Some of their maps might even be able to locate cans of sardines in a sprawling grocery store. 

FastMall is one of the companies.

Users see a floor plan of a shopping mall, for example, with stores indicated by name. Escalators, exits, restrooms and elevators are also marked.

FastMall has a search engine to help users find stores on its maps. Enter “Banana Republic” and the service places a pin on the map to show the store’s location. Tap the “take me there” button and the service plots a route to the destination. To find the nearest restroom, all users have to do is shake their phone. 

A great thing is that many of these services are free: PointInside, FastMall and Micello, which work on the iPhone, iPod Touch and iPad. PointInside is also available for many Android phones.

Using Google to record a phone call

The New York Times explains how:

First, Google can only record calls you receive via Google Voice, not those you dial out yourself. Second, Google announces to all parties that the call is being recorded, so you can’t use it to trap  callers. (Recording a call without the consent of all parties is illegal in some states. Recording a call without anyone on the call knowing it is a federal crime.)



To set up call recording, you must create a Google Voice account. If you’ve already got a Gmail or an iGoogle account, you can use your existing user name and password. Or, you can create one when you first use Google Voice with your browser. The service will give you a Google phone number, with an  area code that may differ from the one on your phone. Then, it will prompt you for a cellphone or land line number where incoming calls to your Google number will be forwarded.

Recording is easy. At any time during an incoming call, press 4 on your phone. A lady’s voice will announce to everyone on the call, “This call is now being recorded.” Continue with your call. After you hang up, Google Voice, whose interface looks a lot like Gmail, will create an inbox entry for the recorded call. You can click to play it in your browser, or download it to your computer as a plain old MP3 file. It’s a lot easier than trying to take notes while you talk, and – provided your caller doesn’t mind being recorded – it’s much less disruptive.

How to find a good cell phone carrier

I have a POP -- plain old phone. I don't text with it; for some reason it's nearly impossible. It's supposed to have a good camera, but I don't use it. It's not good at telling me I missed a call; sometimes I get it a day later. I don't have a smart phone, because I'm not smart enough.

All I want is for it to put through a call when I want to call someone. It does. I'm on the Verizon network, which around here is better than AT&T. I was driving down Main Street in our little town a few years ago and lost the signal three times on AT&T.

I remember sitting at the computer in my house a few years ago and being unable to get a signal. But if I leaned to the left just a bit I could get one.

So I switched, based on word of mouth. SmartMoney has an article describing some other ways to make the decision. The one I like best: throw a party and have everyone bring their cell phones. Check them out.

Here are some others:

There are applications such as CNET’s cell coverage maps and BillShrink’s plan comparison tool out there to estimate signal strength down to the zip code. Those applications and carrier call quality ratings aren’t foolproof, says Kirk Parsons, the senior director of wireless services at J.D. Power & Associates, because reception can vary by block. This, of course, is all subjective. People on a network with wide reports of problems are more likely to notice those misconnections, he says, “And some carriers do a better job of managing customers’ perceptions than others.”

Carriers will let you out of a new contract penalty-free within the first 14 to 30 days. You’ll most likely want to port your number over, but be aware of the timing: if your existing contract isn’t up yet, that will trigger an early termination fee. Use the trial period to test your phone at home, in the office and other places you frequent – it may sound obvious, but a surprising number of people buy a new phone before going on vacation or some other shift in their usual schedule. Not enough bars? You’ll owe only for plan charges during that trial period, whatever plan you sign up for… Of course, then you’ll have to go through the process of porting your number and trying again with another carrier.

Do you really want to insure your cell phone?

Notice how when you buy a toothbrush the salesperson will try to sell you an extended warranty for it? Here's a rule of thumb: when someone is trying hard to sell you something, they're not doing it out of the goodness of their hearts.

Here are some numbers from SmartMoney:

What’s behind the proliferation of policies? For the companies that write them, they can be extremely profitable, says John Rost, founder and chief executive of Fiesta Insurance Franchise. Insurance is designed so we can all pay a little bit so that a small fraction of us can be covered in the event of a disaster. But many of these non-catastrophic policies don’t quite work that way. Between premiums and the deductible, customers with cellphone insurance could end up paying the insurance company more than it would cost to buy a new phone outright. And acccording to some estimates, the profit margin on extended warranties – basically, a form of insurance to protect your gadgets beyond what the manufacturer’s warranty covers – is a whopping 50%.

Ouch. The answer is to self-insure, not for anything catastrophic like your house or life, but your cell phone ... ?

With average premiums around $5.64 per month, according to Citizens Utility Board, cell phone insurance is cheap. But even with the coverage, losing your phone can still be expensive. The policies usually require a deductible of up to $100, in addition to the premiums, and there are often exclusions for common mishaps like cracked screens. Plus, some cell phone issues are covered by the manufacturer’s warranty anyway, the average cell phone isn’t all that expensive, and the insurance company might replace your phone with a refurbished model rather than a new one. “It’s not worth it,” says Schwark Satyavolu, co-founder and CEO of BillShrink.com.

Cost to “self-insure”: $100 - $600. To cover yourself, you simply want to save enough to replace or repair your phone. The average phone repair usually ranges from about $30 to $100, but new phones without a contract are more expensive. Standard phones cost $189 on average, while BlackBerries, iPhones and other smartphones can run up to $599, according to an October 2010 BillShrink.com analysis.

For a long time I thought about insuring my hair against loss, but it's too late -- a pre-existing condition.

A map of online communities

From xkcd.

Visit the original for a clickable version.

About those "slow script" messages

I've gotten a couple of those lately and wondered what they were -- assuming the worst. They happen when you're browsing and a page is taking a long time to load. The New York Times explains:

Web developers typically use scripts for working with ActiveX controls, performing database queries, running Adobe Flash animations, displaying menus or serving up advertisements on the page you just landed on. Most browsers, including Internet Explorer, Mozilla Firefox and Apple’s Safari, have a built-in alter timer that goes off whenever a script running on a Web page exceeds the amount of time the browser has given it to perform — usually from 5 to 10 seconds.

Web pages that need to download a lot of data like video and animated graphics often trip the script alarm. The browser alert box gives you the option to stop running that script so that the browser doesn’t get hung up waiting for it to finish. Some scripts are just complex and slow, but some are badly written and slip into an endless loop.


Stopping the script shouldn’t cause any problems, but the page may not work properly. If you want to try some troubleshooting, press Control+F5 to refresh the page and see if the error message reappears. If you have a lot of browser tabs open to pages that may also be running scripts to refresh mailboxes or automatically update themselves, try closing those as well before reloading the page to see if the error message goes away.

Security software my be slowing things down as well, especially if you have it set to investigate JavaScript and other Web-page code for malicious activity. If you do, try disabling that setting temporarily to see if the slow-script error goes sway. If it does, you may just have ignore the warning and wait a little longer for the software to scan.

Microsoft has more information on the error, along with a workaround that simply lengthens the amount of time before the error message appears here.

So it's okay to drive and text?

Laws banning texting while driving actually may prompt a slight increase in road crashes, research shows. Man bites dog.

"Texting bans haven't reduced crashes at all," says Adrian Lund, president of the Insurance Institute for Highway Safety, whose research arm studied the effectiveness of the laws.

Researchers at the Highway Loss Data Institute compared rates of collision insurance claims in four states — California, Louisiana, Minnesota and Washington — before and after they enacted texting bans. Crash rates rose in three of the states after bans were enacted.

The Highway Loss group theorizes that drivers try to evade police by lowering their phones when texting, increasing the risk by taking their eyes even further from the road and for a longer time.

There's some debate about this.

Lund: The findings "call into question the way policymakers are trying to address the problem of distracted-driving crashes," Lund says, calling for a strategy that goes beyond cellphones to hit other behaviors such as eating and putting on makeup. "They're focusing on a single manifestation of distracted driving and banning it," he says.

Transportation Secretary Ray LaHood: "Between 2005 and 2008, distracted driving-related fatalities jumped from 10% to 16% of all traffic fatalities," he says. "In 2009, for the first time in four years, distracted driving fatalities stopped rising, remaining at 16%. ... Tough laws are the first step and enforcement must be next. We know that anti-distracted-driving laws can be enforced effectively."

Here's a number to keep you from going crazy in the car: Last year 5,474 people were killed and another 448,000 injured in crashes involving distracted driving, defined as operating a vehicle in a careless or inattentive manner, the government says.

Keep this in mind: The National Highway Traffic Safety Administration says just a fraction of the 5,474 people killed and 448,000 injured in crashes involving distracted driving last year involved cellphones: 18% of the fatalities and 5% of the injuries. That means that most distracted driving crashes involved some other behavior.