Where's the SLR-style compact camera?

But for the enthusiast who wants a smaller alternative to the bulky but high-performance SLR, or single-lens reflex, camera, it's slim pickings.

"There's a gap in the market for a certain class of camera for somebody who's got a digital SLR and wants those capabilities at the times they're not carrying an SLR," said Lyra Research analyst Steve Hoffenberg.

Digital SLRs bring a host of improvements over compact cameras: they start up faster, shoot more frames per second, produce "raw" images that retain all the data from the image sensor, offer manual control over numerous settings, and have large sensors that work better in dim light or when trying to freeze action. The SLR market is fast-growing and today dominated by Canon and Nikon, but also has contenders in Olympus, Pentax, Panasonic, Sony and others.

But SLRs are too bulky for a purse or pocket. Even serious shutterbugs often leave them behind when scaling mountain peaks, traveling or just heading to work.

"I like photography, but it's a passion, not a job. I like first of all to take my camera with me always, even if I'm (on) my bicycle," said Stefano Di Cecio, who lives in Italy's Tuscany region. But he's used film SLRs, and he wants raw image support, manual controls and a good lens, so he settled on the Panasonic DMC-LX2.

A pie-in-the-sky compact camera would have a fast, high-quality lens that reaches as wide as 28mm. It would have a large sensor that emphasizes sensitivity over megapixels. Raw image support so the photographer gets more than just stripped-down JPEGs. An optical viewfinder for shooting in bright conditions or preserving battery life. A quick shutter response. Maybe a hot shoe to accommodate an external flash. And a price tag under $500.

That's probably too big an engineering challenge for a single model. But some camera makers have come close.

Some options
Possibly the compact camera closest in design to an SLR is Canon's PowerShot G7, the latest in a series of products aimed directly for the SLR enthusiast. A Tokyo resident whose Flickr username is Leopard Gecko uses his to shoot close-ups of insects and flowers--but like many camera reviewers, he wishes it came with the raw image support that predecessors like the G6 had.

Another option is the Nikon Coolpix P5000, which is considerably smaller than the PowerShot G7 but, like it, has a "hot shoe" to mount an external flash. However, it too lacks raw support.

Bulkier models such as Olympus' SP-550 UZ and Fujifilm's Finepix S6000fd have long zoom ranges and raw-image support, but they're not so easily to place in a pocket, and long zoom ranges typically take a toll on image quality. Ricoh's GX100, which supports raw files but is compact, has won some ardent supporters but isn't widely available in the United States. And Sigma's forthcoming DP1 uses the same higher-end Foveon image sensor as its big brother, the SD14 SLR, but the compact model has a fixed 28mm focal length lens.

Some experts have called for a better compact camera--Mike Johnston of the Online Photographer blog has called it the "decisive moment digicam," and Thom Hogan, author of the Nikon DSLR Report, has described in detail his ideal small camera with a large sensor.

Hogan estimates hundreds of thousands to millions of such a camera could be sold annually. That may sound small, but it's likely to be a nice niche, he said.

"Digital SLR growth is hitting the plateau already and will level off to normal or worse within the next year or two. Meanwhile, there are unserved niches where you could make your own growth, get almost the same unit volume and retain high product margins," he said. "High-quality compacts is one of them."

But there's a good reason manufacturers might pause before aiming a compact camera at SLR aficionados, Hoffenberg said: they probably already have one, even if it's not necessarily high-end.

"Lyra's research shows the vast majority of digital SLR owners already owned a point-and-shoot digital camera before they purchased an SLR," Hoffenberg said. "Just about half of digital SLR owners had multiple point-and-shoot cameras in the household--two or more."

Enough megapixels already
Some believe a step in the right direction would be to use larger image sensors--perhaps even as large as those in lower-end SLRs--or at least sensors with more sensitive pixels. The race to squeeze as many pixels as possible onto sensors has increased unwanted colored speckles called image "noise," several experts contend.

Stefano Mattia, who lives in Rome, is happy with his Panasonic DMC-LX2--except for the sensor.

"Take the LX2 and replace its sensor with one which could provide virtually noise-free pictures up to ISO 400 to 800, and that would be the perfect compact camera," Mattia said. "I'd rather have fewer megapixels than noisy photos."

Fewer megapixels also would reduce some burdens of processing and saving images, potentially improving responsiveness. But consumers would have to understand the argument that a particular camera makes up in quality what it lacks in quantity, and that could be tough, judging by the unceasing increase in sensor megapixel counts.

Enthusiasts frustrated with higher-end compact cameras have grounds for hope that camera makers will better meet their needs, though.

"What Nikon saw with the P5000 and Canon with the G7 is that particular niche does now appear to be growing big enough that it can support some models in the market," Hoffenberg said.