When the moment comes to take the perfect picture of a snowy mountaintop, Fourth of July fireworks or soccer goal in midkick, most people forget about these features or don’t know how to use them. And while many digital cameras can now detect faces and make sure they are in focus, they can’t tell whether that face is smiling or not. The results aren’t bad, but they could be much better.

Sony’s Cyber-shot DSC-W170 uses Smile Shutter Mode to snap pictures when a subject smiles.

This week, I tested three new digital cameras that claim to do the thinking for you. Some digitally analyze the scene you’re about to capture, automatically choosing the setting that would take the best picture. Others can detect when a subject is smiling so as to automatically know when to snap the photo. One camera even attempts to digitally alter frowning faces into smiles, with amusing results.

I tried out Sony’s $300 Cyber-shot DSC-W170, Kodak’s $250 EasyShare Z1085 IS and Olympus’s $200 FE-340. Only the Sony (SNE) includes all three of the aforementioned features; the Kodak (EK) has scene detection, and the Olympus (OCPNF.PK) camera has built-in smile detection. I found the automatic scene detection offered in the Sony and Kodak cameras to be the most useful feature for everyday photos. It improved my photos and didn’t require any extra adjustments. I handed the cameras to other people to take pictures, without having to change any settings.

The automatic smile detection offered in the Sony and Olympus cameras was fun to use and could be especially helpful for families whose young kids never seem to smile at the right moment. But it didn’t work consistently and had trouble detecting my bearded boss’s smile and even that of a beard-free colleague.

I found Sony’s frown-fixing tool, which is called Happy Face Retouch, to be rather unusual. It took already captured images of my friends’ faces and turned their frowns or ambivalent looks into smiles, but didn’t adjust the subjects’ eyes. Though this was good for laughs, the eerie-looking grins pasted on faces reminded me of painted-on clowns’ mouths. And some attempts to retouch a face couldn’t detect the face to alter it. But a handful of the Happy Face Retouches looked somewhat natural.

Similar Specs

These cameras boast many similar specifications. All three use 5x optical zoom lenses, and the Sony Cyber-shot DSC-W170 and Kodak EasyShare Z1085 IS each have 10.1 and 10 megapixel image sensors while the least expensive Olympus FE-340 has 8 megapixels. The Sony and Olympus both have generous 2.7-inch viewing screens and almost identically sleek builds, though the Sony is the only one of these three cameras to have an optical viewfinder.

The Kodak’s viewing screen is slightly smaller than the other two digital cameras, measuring 2.5 inches, but its build isn’t nearly as compact as the others. It reminded me more of small, high-end SLR camera, with its comfortably large hand grip, a settings knob on the top edge of the camera, and a protruding zoom lens.

Sony’s Happy Face Retouch feature digitally changes facial expressions into smiles, but all it did was make me look unnatural and awkward.

Kodak’s EasyShare Z1085 IS takes Secure Digital (SD) memory cards, which are more common than the Memory Stick and xD cards that work in the Sony and Olympus cameras, respectively.

The Kodak and Sony digital cameras have different names for their automatic scene-detection features. By default, the Kodak camera works in Smart Capture Mode, which includes intelligent scene detection, capture control and image processing. I focused on the camera’s scene detection, which automatically determines whether the photo should be taken in Macro, Text (for shots of text in a book, for example), Face, Landscape or Night settings.

Icon on the Screen

I snapped pictures around Washington, D.C., noting a tiny icon on the camera’s screen that indicated which of the five scene modes was being used to capture the photo. A flower icon indicating Macro appeared on my screen when I stooped to get a close-up shot of a tulip, and an icon of a dark sky and stars showed on the screen when I took photos at night. The camera’s flash, focus and exposure changed according to the type of photo.

The Sony camera uses what it calls Intelligent Scene Recognition to decide which settings should go along with certain photos. Like the Kodak, icons on the Sony’s screen indicated the scene settings that were automatically deemed appropriate, including Backlight, Backlight Portrait, Twilight, Twilight Portrait and Twilight Using a Tripod.

The Sony’s Intelligent Scene Recognition isn’t on by default like Kodak’s feature. Instead, it must be turned on from within a menu, but once on, it stays on until you turn it off. ISR can be used in either Auto or Advanced mode; Auto takes a single photo with automatically determined settings, while Advanced takes two shots — one with manual settings you can choose and another shot immediately following the first with automatic settings according to what the camera thinks is best.

I experienced surprising results with the Sony Cyber-shot DSC-W170 and Olympus FE-340 while testing their automatic smile-detecting functions. My friends thought I was joking when I told them the camera would take their picture only if they were smiling. When the flash went off multiple times as they kept smiling, they were intrigued by this feature.

Sony’s version, which it calls Smile Shutter Mode, is easy to switch into by turning a dial on the camera to a smiley face. Once this setting is chosen and the camera’s shutter button is pressed, the Cyber-shot will search for smiles in its subjects, and will take photos whenever it detects a smile. Settings within this mode can be set to specifically detect an adult’s smile or a child’s smile, and the degree of smile can be set to low, medium or high; I kept things simple by leaving the smile detector on default settings.

Capturing Smiles

Olympus calls this feature Smile Shot, capturing three rapid shots in a row to make sure everyone’s smiling. The idea of taking three shots would be extra helpful with an indecisive baby, but most of my friends were able to hold their smiles, which produced three almost exactly identical shots each time someone smiled. Smile Shot is harder to get to in a pinch compared with the Sony: it’s buried in a list of 13 settings on the Olympus when the camera is set in Scene mode.

The Olympus seemed to be a bit slower than the Sony when it came to detecting smiles, but both had trouble with bearded men and even some folks without beards. And people felt silly standing around with a smile on their faces waiting for the camera to finally work. Closed-mouth, no-teeth smiles were harder for these cameras to detect, but not impossible. In group situations, the Olympus camera will focus on whoever’s face appears largest, which could mean the person closest to the camera, while the Sony takes a picture whenever anyone in the group smiles.

Putting a Happy Face On

If someone isn’t smiling, Sony’s Happy Face Retouch tool can come in handy, but don’t count on liking the results. In a group shot of five friends, two people who weren’t smiling put a bit of a damper on the whole shot. I used Happy Face Retouch, but it picked up on only one of the nonsmiling faces, turning a confused look into a smile that looked passable. But other results weren’t usable. A serious-looking shot of me deliberately not smiling looked freakishly unnatural after the touch-up, mostly because the rest of my face didn’t join the smile. I looked more like someone who had received too many Botox treatments.

Sony says that, in group shots, it can detect and change up to eight faces, but in my tests it usually changed only one. This retouching tool is also difficult to find: It took me 16 button presses to change each image into a smile — or what Sony calls a smile. A few times, Happy Face Retouch couldn’t identify a face in the photo, even when just one person stood in the frame.

These digital cameras took good photos, overall, and are fun to use because they take pressure off the photographer. I found the automatic scene-detection tools of the Kodak and Sony to be the most realistic and useful offerings, and I’m sure it won’t be long before automatic scene detection becomes as commonplace as an automatic flash.

The chart below compares features of the three cameras described. Click on it to make it larger.

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It’s a good time to be in the market for such a camera. According to research from Olympus, unit sales for these gizmos has grown about 30% in the past two years, while dollar sales grew at about half that rate, indicating declining prices and improved technology. In fact, digital-camera prices have dropped an average of $30 over the past 12 months.

This guide offers an overview of the basics that you’ll need to know when buying a digital camera. It also explains many of the fancy features that are popping up on these devices, such as facial recognition — a camera’s ability to detect when faces are being captured in photos, thus appropriately adjusting exposure, focus and flash. This guide isn’t geared toward hobbyists, but rather toward average users who want good quality photos but don’t want to struggle with confusing product specs and promotions.

Point and Shoot, or Flaunt and Pocket

As you begin looking for a camera, selecting a preferred size and shape will help narrow your choices. Like iPods and cellphones, stylish pocket cameras are fashionable accessories; some come in shades like Precious Rose or Noble Blue. These pocket models, designed with emphasis on small size, are as easy to carry as they are to use for taking good photos: most offer seven or eight megapixels each, a 3x or better optical zoom lens and a stunning viewing screen. Good examples include Sony Corp.’s $400 Cyber-shot DSC-T100 or Nikon Inc.’s $300 Coolpix S50.

If you don’t mind sacrificing style for a camera that’s sturdier in your hand but bulkier in your purse, point-and-shoot models will be more your speed. On average, these cost less than their showy cousins. They’re more likely to have protruding zoom lenses that don’t collapse entirely into the camera body and often feature larger buttons. More point-and-shoots offer optical viewfinders, which have become practically extinct on pocket digicams where real estate is scarce. Examples of point-and-shoots with optical viewfinders include Eastman Kodak Co.’s EasyShare C653 and Canon Inc.’s PowerShot A460-both cost $130.

A third category of digital cameras, the single-lens reflex or SLR, continues to be marketed to regular consumers rather than to the photography enthusiasts for whom they were originally intended. SLR prices have dropped a couple of hundred dollars in the past year, but many models still start around $800 and come with detachable lenses and flashes. Average users can steer clear of SLR cameras.

Megapixels

Most cameras today offer anywhere between six and 10 megapixels; cameras with four megapixels or fewer are rather rare. But while higher megapixel counts are easy to find for less money, such as Hewlett-Packard Co.’s $300 PhotoSmart R967 with 10 megapixels, such intense resolution is really only necessary if you plan to heavily edit or blow up your photographs for jumbo prints, which most people won’t be doing.

Zoom Confusion

While most camera makers offer clearer marketing strategies now than a year or so ago, some still try to dupe consumers by listing only a camera’s total zoom — the optical and digital zoom multiplied together to create a larger, more impressive number. The truth lies in optical zoom, an enhancement made by a physically moving lens, not digital zoom, which instead magnifies a photo using the camera’s digital circuitry.

This year, companies also created a new category for cameras with 10x or 12x optical-zoom lenses — these are often referred to as high zoom digital cameras. In reality, a camera with about a 4x optical zoom is sufficient for most people.

Facial Recognition

This category is likely to become more popular. Facial recognition makes the camera smart enough to recognize that the subject contains a face and must be captured with the correct balance of color and lighting. Sony’s Cyber-shot G1 can detect up to eight faces in one image; Canon’s technology can detect up to nine per shot.

Image Stabilization

Image stabilization, or IS, was once only available in high-end SLR cameras. Now, almost all of the top-name consumer digicams offer this because without optical viewfinders, users must shakily hold cameras out to look through viewing screens. Referred to as antishake or vibration reduction by some manufacturers, there are three kinds of IS: optical and mechanical image stabilization, which physically steady a camera even when your hand is shaking, or digital image stabilization, which can improve a shot when the photographed subject is moving.

Some cameras, like the $250 Olympus Stylus 760, offer dual IS. This means the camera is equipped with both digital and mechanical or optical image stabilization, the best of both worlds. If you’ll be using a camera specifically for shots of moving objects, digital IS will work.

Storage — on Your Camera or on a Web Site

The cost of memory cards has dropped by half compared with last year: one-gigabyte memory cards now only cost about $30, and $50 two-gigabyte cards are even more popular thanks to people who want to record videos for uploading and sharing on Web sites. Data can be transferred from these cards by plugging them into a computer using an adapter or a card slot, or cameras can be connected to PCs with USB cords.

Now, Kodak, Nikon and Sony offer cameras with wireless Internet connection capabilities, or Wi-Fi. This allows you to take pictures and, when connected to a Wi-Fi hotspot, upload them directly to a Web site for sharing or storing, saving you the step of transferring the images to a computer first. These cameras are the $200 EasyShare One from Kodak, Nikon’s $350 Coolpix S50c and Sony’s $600 Cyber-shot DSC-G1.

Although using Wi-Fi in a digital camera is a smart idea, it could be a real drain on your camera’s battery. Wi-Fi is by no means a necessary feature, but some people will find it a useful add-on.

Battery Tips

Camera battery life can be affected by new features like extra-large screens — especially those that can play slide shows of your photographs — built-in Wi-Fi and even in-camera editing, which requires your camera and LCD screen to be on for longer periods. If you rarely take shots indoors, your flash will likely be used less, which might help your camera’s battery life. A spare battery is useful, and some cameras will work with drugstore batteries for the sake of convenience.

In-Camera Editing

The large, bright LCD viewing screens on cameras — some of which measure up to three inches or even three and a half inches diagonally — encourage everyday photogs to share their shots. To make even these images look better, camera manufacturers are incorporating in-camera editing for fixing mistakes on the spot, without a computer.

Cameras from all of the major manufacturers now enable red-eye fixes either as the photo is captured or after the fact. Companies such as Kodak offer zooming, cropping and panoramic shot stitching, while H-P cameras offer touch-ups like blemish-removing and ways to make a subject look slimmer.

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The digital camera category is exciting right now, as these portable devices become more like computers thanks to in-camera editing, greater memory and built-in Wi-Fi. But remember that your photos come first, no matter how many bells and whistles are added to a camera.

Edited by Walter S. Mossberg

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