Imaging tech

JPEG XR, an image format created by Microsoft that promises a number of advantages over JPEG, has cleared a key standardization hurdle.

The Joint Photographic Experts Group, which standardized the original and still ubiquitous JPEG format, sent JPEG XR to the "final phases of standardization" after a vote at a January meeting, the group said Thursday. That means the standard's future is more certain.

"The committee expects the JPEG XR International Standard to be published later this year," the group said.

JPEG XR offers a few advantages over JPEG, according to Microsoft. For one thing, … Read more

Panasonic's $670 G1 and Olympus' $540 E-520 and $450 E-410--that show both the advantages and disadvantages of the Four Thirds standards the companies use.

The Four Thirds system governs image sensor sizes and the mounting mechanism for interchangeable lenses on the companies' SLR cameras, and the companies announced a new variation called Micro Four Thirds for smaller cameras that have SLRs' interchangeable lenses but not SLRs' "reflex" mirror, which directs light through an optical viewfinder before a shot is taken.

Four Thirds SLRs have a smaller sensor than lower-end SLRs from market leaders Nikon and Canon, which poses image quality challenges because there's less surface area to gather light. However, the sensor size is the same for Four Thirds and Micro Four Thirds, which means that cameras using the latter have a much larger sensor than typical compact cameras have. … Read more

FixMyMovie, an online service that let people improve the quality of their videos, is going offline.

"We're shutting down FixMyMovie.com on December 31, 2008. In its place, we're launching a new Windows desktop application, code-named Carmel, which will be released in the first quarter of 2009," said MotionDSP, which runs the site, in an e-mail to site members Friday. "If you have uploaded any videos to FixMyMovie that you'd like to keep, we recommend that you use the 'Download' option before December 31 for each fixed movie that you'd like to save.&… Read more

One verdict is in on Canon's EOS 5D Mark II: its sensor ranks very high on DxO Labs' test of sensor performance.

The black-spot issue notwithstanding, Canon's new full-frame SLR came in at fourth place with a score of 79.0, bumping Sony's 78.9-scoring Alpha A900 down a peg but still trailing Canon's top-end EOS-1Ds Mark III at 80.3. Nikon's D700, the closest rival to the 5D Mark II, is a notch ahead at 80.5.

More relevant for the potential upgrade market, new Canon SLR's score is significantly better from that of its predecessor, the 5D, whose score is 70.9. On a pixel-by-pixel basis, the 12.8-megapixel 5D's sensor actually has a lower signal-to-noise ratio, but when measured over an entire 8x10 print, the 5D Mark II's higher 21.1-megapixel resolution wins on that measurement.

The DxOMark Sensor test measures how well a camera's sensor fares when it comes to dynamic range, color depth, and low-light performance. The test doesn't measure any number of other camera issues such as autofocus, value, or image processing. But it's still useful given DxO Labs' engineering rigor and the central role a sensor plays in the abilities of a camera.

Pixel-peepers have been devouring DxO's new statistics; the curious can try this link to a comparison of the 5D Mark II, Nikon D700, and Sony A900. However, it should be noted, DxO Labs considers that scores must be at least of 5 points apart to be significant.

There's been much discussion about whether the $2,700 5D Mark II performs better than the $6,500 1Ds Mark III, which has the same resolution. The DxOMark tests give the edge to the top-end model based on its better color and dynamic range--the ability to capture both bright and dark regions--but the 5D Mark II wins out in low-light performance. Digging deeper into the charts, though, the 5D Mark II fares better in dynamic range at higher ISOs.

All these cameras perform better than the common herd by virtue of full-frame sensors measuring 36x24mm, the size of a full frame of 35mm film. Most digital SLRs have a smaller sensor that can't capture as much information overall, but those models are vastly more affordable. … Read more

A correction was made to this story. See below for details.

DxO Labs, a French company with deep experience measuring cameras' technical performance, has launched a Web site called DxOMark.com that features detailed information on the performance of the image sensor at the heart of many higher-end digital cameras.

Many Web sites and magazines measure camera image quality with varying degrees of rigor, typically examining either the JPEG that the camera produces or a processed version of the camera's raw. But with its DxOMark Sensor measurement, DxO takes a new approach by judging the sensor performance based on the unprocessed "raw" image file from higher-end cameras such as SLRs.

That's significant, because raw images typically must go through a conversion process called demosaicing before they're useful for viewing. Most digital cameras capture only a single color--red, green, or blue--for each sensor pixel. Demosaicing fills in the gaps in this colored checkerboard pattern so each pixel gets all three color components, but this processing stage can disguise sensor performance.

The detail-obsessed camera crowd has begun eagerly chomping on the new data. On Sunday, there were 220 mentions of DxOmark on the Digital Photography Review forums, a popular location for impassioned technical discussions.

New tests coming More measurements are coming, added Nicolas Touchard, vice president of marketing for DxO Labs' image quality evaluation business. First, in two or three weeks, will come measurements for medium-format digital camera sensors from companies including Hasselblad, Mamiya, Phase One, and Leaf. Then will come more high-end compact "bridge" cameras.

DxOMark Image Processing for the camera's computer, whose job it is to perform tasks such as converting raw images to JPEG, and DxOMark Optics for lenses.

The latter measurement will go beyond most lens tests by showing how well each lens works on each camera rather than one or two reference models. DxO takes that approach because lenses behave differently because different cameras have different attributes such as the geometry of the microlenses that help each sensor pixel gather more light, Touchard said.

DxO makes a business out of detailed measurements of camera performance, selling the data to camera and chip companies and incorporating it into its own DxO Optics Pro raw-processing software for photographers. So why give some of the data away for free on a Web site? Publicity.

… Read more

In a surprise announcement that underscores how dedicated Sony has become to its digital camera division, the company says that it has developed a full-frame, 35mm-format 24.81-megapixel CMOS sensor. As if a high-rez, full-frame sensor isn't good enough, Sony says that the new sensor will be able to yield an impressive 6.3 frames per second. By contrast, Canon says its 21.1MP EOS 1Ds Mark III can shoot up to 5fps. The strange part about the new Sony sensor is that it only offers 12-bit output, while higher-end SLRs, such as Canon's 1Ds Mark III and … Read more

LAS VEGAS--You may not know it from the outside, but digital cameras are getting something like an eye transplant.

Deep within every digital camera is a sensor chip whose job it is to capture light. Most camera sensors today use CCD (charge-coupled device) technology, but a newer approach called CMOS (complementary metal oxide semiconductor) is catching on, particularly at the high end of the market.

CMOS advantages can include lower noise, lower power consumption, lower price, and faster response times. In the prestigious and fast-growing digital SLR (single-lens reflex) camera market, Canon and Olympus have used CMOS sensors for years, … Read more