Changes in cameras and photography are often incremental: a faster autofocus, a smaller body, a better sensor.
Which is why change -- real change -- is so surprising when you encounter it. The startup Lytro has introduced a kind of camera that makes a significant leap forward.
What's the big deal? With Lytro's camera, you can focus on any point in an image taken with a Lytro after you've shot the picture.
The problem? It will not be available until after the holidays. (And the Lytro works only with Macs, but Windows software is in development.)
When viewing a Lytro photograph on your computer, you can simply click your mouse on any point in the image and that area will come into focus. Change the focal point from the flower to the child holding the flower. Make the background blurry and the foreground clear. Change the focal point as many times as you like.
Lytro does this by capturing what is called lightfield data. The technology has existed in research facilities for more than a decade, but early lightfield cameras were the size of a wall unit in your den. Lytro's camera fits in your hand.
By capturing the angle of light beams, all pictures shot with a Lytro camera are also natively 3-D (if you have the display and the glasses). More important, the camera no longer has to focus because it's capturing every focal point, which means there's no focus lag.
Images taken with a Lytro are saved in file sizes similar to regular photos, so you can email and post them easily. Each file contains the viewer software, so friends can see them.
The entire assembly weighs about half a pound. Blue and gray models have 8 gigabytes of built-in storage (about 350 pictures) and cost $399. A red model has 16GB of storage (about 750 pictures) and costs $499.
Orders can be placed on lytro.com, but delivery will not take place until the beginning of 2012.
How to make sure that a Wi-Fi network is secure
When you use a Wi-Fi connection to access the Internet, the data you transmit flies through the air. This allows you to remain blissfully connected at home, in a hotel or in a departure lounge, but it also comes with privacy and security risks. But you can use Wi-Fi securely. Here are tips from the industry group Wi-Fi Alliance on how to keep your data private and your home network creep-free.
●Turn on the security that comes with your home router. Any Wi-Fi router bought in the past six years includes security technology called Wi-Fi Protected Access Version 2, or WPA2, which keeps information private and secure by strongly encrypting it while it travels. But you have to turn on WPA2 to benefit. Make sure you're using WPA2, and not WPA, and certainly not the 11-year-old WEP, which was broken by hackers long ago.
●Set up a strong network password. Wi-Fi Alliance recommends using a password that's at least eight characters long and includes a mixture of upper-case and lower-case letters, along with a couple of symbols or numbers. Avoid including your name, address, router brand name or dictionary words because they can make your password easy to guess or crack.
●Use Web sites that encrypt your traffic. When using a Wi-Fi network, make sure that sensitive Web sites you use encrypt your data. Encryption is occurring if you see "https" in the address bar and almost universally occurs when you make a purchase on a shopping site, bank online or log into a Web-based email service.
●Use VPN technology to encrypt your activity. If you travel a lot and must transmit sensitive data over public networks, it's wise to use virtual private network software, which creates an encrypted tunnel for your data to flow through. If your company does not have a VPN, there are user-friendly and affordable VPNs on the market.