Phase One takes lead in camera sensor test

Medium-format digital cameras, which have larger sensors and higher price tags than even high-end SLRs, didn't fare so well in earlier tests of sensor quality by measurement firm DxO Labs, but Phase One's newly tested top-end technology has risen to the top of the DxOMark Sensor test.

Phase One now rules the DxOMark Sensor roost.

(Credit: DxO Labs)

Phase One's 60-megapixel P65+ camera scored 89.1 on the test, edging out the Nikon D3X, which scored 88, according to data released Thursday. In addition, the 51.7-megapixel Hasselblad H3DII 50, an older model than Phase One's, scored 78.2. Click here to compare the two models and Nikon's D3X.

The DxOMark sensor test measures a camera sensor's dynamic range, color depth, and low-light performance. DxO Labs cautions that differences of less than 5 points aren't really distinguishable, and of course many other factors including price, lens quality, autofocus, and resolution factor into overall camera quality.

The P65+ features the best color performance yet, but DxO Labs said its comparatively good performance in low-light conditions helped it carry the day.

"This Sensor Plus mode utilizes a binning method: The analog signals of 4 photosites are combined to obtain single pixel after digital conversion. This well-known technology allows for higher sensitivity, but with a loss of resolution (1/4). Only very high-resolution sensors can provide this option," DxO Labs said.

Digital camera sensors capture green, red, and blue light with an array called a Bayer pattern.

(Credit: DxO Labs)

DxO Labs bases its scores on the unprocessed raw images from the image sensors, not the more limited but convenient JPEG images that cameras also produce.

DxO's scores haven't been met with universal acclaim. In response to some criticisms and in an attempt to dispel some confusion, DxO has published a boiled-down DxOMark Sensor explanation.

For example, the company has this to say about sensor resolution, an issue that arose when comparing medium-format cameras with large, high-resolution sensors to high-end SLRs: "DxOMark Sensor and resolution are two independent metrics of sensor performance. As a consequence, just because camera A has more pixels than camera B (and thus sees more details) does not mean that its raw DxOMark Sensor score will be better. So before comparing cameras with DxOMark Sensor, it is important to first determine the resolution you are looking for."

[kcotham]

Correct me if I'm wrong, but isn't the D3X a FX format camera? Perhaps I'm missing the point of comparing apples and oranges here.

[gerrrg]

Hmm. Looks like the D3x has a huge advantage on low light ISO, but still lost. Strange weighting of scoring.

[askj113]

I think that's one of the problems people are complaining about, that the D3X is an all around camera you could use to go anywhere in any situation, while the phase one is only going to be used in a fairly narrow set of uses that require photos of that size and quality. Thus, it doesn't need an iso range anything like the D3X, and thus takes a huge knock for it. Comparing the other two qualities they're measured would produce a fairly different score, I think.

[pjk0]

The point of having a simplistic "single number benchmark" is that it will always entail some sort of compromise - the creators of the benchmark get to decide what factors weigh into it and what their relative weights are. If they didn't stay consistent with this, then making relative comparisons would be far more complicated. Very few people are going to pore over charts of 50 different numbers on every tested product in order to make a quick comparison.

But Dx0 provides the raw numbers precisely for this purpose, if you have a particular characteristic you're looking for. For example, the best sensor in low-light remains the Nikon D3/D700, despite the fact that it rates a little lower than the D3x overall due to its lower resolution (12MP vs 24MP) and probably a few other minor details.

What I think is impressive is the overall performance of the D3x, a "35mm style" camera, compared to these "medium format style" competitors. People ******* and moaned when Nikon announced the price of the D3x ($8000), but that Hasselblad sells for $30,000, and the PhaseOne P65+ (JUST THE BACK, NO CAMERA) for $40,000!