benchmarking

Google's latest version of Chrome has claimed the lead in my JavaScript speed tests, but Apple's new Safari 4 beta is the first browser to challenge it on Google's own performance benchmark.

JavaScript is a programming language that powers not just innumerable ordinary Web sites, but also many Web-based applications such as Google Docs. With the computing industry's major push to cloud computing, Web application performance is increasingly important, and there's a race on to see who's got the best JavaScript engine. JavaScript engines even have become a named feature, with Chrome's V8, Firefox's TraceMonkey, Opera's Futhark and upcoming Carakan, and now the Safari's newly branded Nitro, which is Apple's version of WebKit's Squirrelfish. … Read more

Sure, most AV receivers have "good enough" built-in headphone amplifiers, which are fine for occasional listening.

But if you regularly listen to a decent set of headphones over your home theater system or computer, I recommend moving up to a high-quality headphone amplifier, like Benchmark's DAC1 USB ($1,275).

AV receivers' headphone amps, even on $1,000+ models either sound anemic, with little or no bass, or they're muffled sounding things. Whenever I review high-end headphones, I always plug them into an iPod, AV receiver, and a dedicated headphone amplifier, just to see how they perform in different contexts. But headphones always do their best when plugged into a good headphone amp.

Benchmark is one of the few manufacturers of professional audio gear that has consistently wowed audiophiles. The company offers a range of headphone amplifiers, and I reviewed the Benchmark DAC1 USB when I tested the Denon AH-D5000, Grado GS-1000, and Ultrasone Edition 9 luxury headphones for Home Entertainment magazine. … Read more

Unisys may have written Itanium's epitaph on Wednesday--at least for some of the largest server vendors.

Colin Lacey, vice president of Systems and Storage at Unisys, discussed in a phone interview why Unisys--one of the top 10 U.S. server vendors--doesn't see a future for Itanium, including the long-delayed quad-core Itanium "Tukwila" processor.

Lacey said Itanium's appeal has almost vanished for many vendors in server industry. "It's appeal has certainly narrowed down. It's almost exclusively down to a single vendor," he said, referring to Hewlett-Packard. "The current shipping platform is … Read more

It looks like Canon and Nikon weren't blowing smoke when they said their high-end SLRs cameras will compete with medium-format digital cameras used almost exclusively by professionals.

Given the image quality advantages that SLRs with larger "full-frame" sensors have over mainstream and much less expensive models with smaller processors, one might have expected another quantum leap from costly high-end medium-format digital cameras with sensors twice the area of top-end SLRs. Not so, according to new DxOMark Sensor test results set for release Tuesday by French test and measurement firm DxO Labs.

The company tested image sensors from several medium-format cameras--the Mamiya ZD Back, Leaf Aptus 75S, Hasselblad H3DII 39, and Phase One P45+. These are the sorts of cameras used by fashion photographers and others who need lush tones, fine detail, and lots of megapixels to handle big photos such as magazine spreads.

But none outperformed the Nikon D3X SLR, whose score of 88 gives it the current top rank on DxO's sensor tests. … Read more

With everything going green, it was only a matter of time before we added more power consumption testing in the labs. With all the advancements in graphic cards--multiple GPUs, multiple power connections, Crossfire, and SLI--they're now one of the biggest energy hogs in your rig. Our goal is to look at GPU power consumption and measure power vs. performance vs.cost.

The test bed is Intel-based, with a Core i7 965 processor at 3.20GHz and 4GB of DDR3 SDRAM at 1066MHz. The meter used to measure the system's power is a Watts up? Pro ES. Watts up? … Read more

It's not a surprise that the Nikon D3X, the company's brand-new $8,000, 24.5-megapixel SLR, tops DxO Labs' sensor performance test. What is a surprise is the margin by which it leads its rivals from Canon and Sony.

When the French firm unveiled its DxOMark Sensor benchmark test last year, Nikon's D3 was the top scorer at 80.6, a composite number that represents various performance features. Very close on its heels were Nikon's D700 at 80.5, Canon's EOS-1Ds Mark III 80.3, and later Canon's 5D Mark II at 79 and Sony's Alpha A900 at 78.9.

All those cameras were close, but the D3X stands apart with a score of 88. The result shows how much ground Nikon has made up on Canon, which has dominated high-end digital SLR technology. … 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

On Tuesday, Mozilla released Firefox 3.1 beta 2 and Google released Chrome 0.4.154.33, so it's time for the latest installment of JavaScript performance testing.

Here's the highlight: Though Firefox remains the leader on the SunSpider test, with a score of 2,110, Chrome edged very close with 2,140. A lower score is better; because of some variation in results, the numbers I quoted are an average of several runs.

Firefox and Chrome aren't the only browsers out there, but they're interesting to compare for a few reasons. First, they're both … 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