Excellent dynamic range helps Pentax's new flagship camera stand out from its predecessors and current competitors.
Pentax has leaped to a commanding lead over many rivals when it comes to image sensor performance with its latest high-end SLR, the K-5.
That is a notable sixth-place ranking of all the cameras on DxO Labs' list, especially because the top 5 cameras are pro models costing thousands of dollars more than the K-5. The result came, in large measure, from the K-5 sensor's excellent dynamic range, a measure of its ability to capture details in both bright and dark areas of an image.
The K-5's Sony-built sensor spans a notable range of 14.1 exposure values at ISO 80, trouncing direct rivals such as the 11.7 of Canon's 7D and 12.2 of Nikon's older D300s. That score is all the more notable given that the K-5 even outscores some cameras with larger full-frame sensors.
However, it's clear that there is plenty of new competition coming. Nikon's new D7000, for example, has a dynamic range of 13.9 and largely matches the K-5 through much of its ISO range. Notably, the sensor in Nikon's cheaper D7000 scores 80 on DxO's tests. Those tests, it should be noted, only measure the sensor, not countless other important camera details such as price, autofocus, lens and accessory selection, durability, performance, and user interface.
Pentax's 16.3-megapixel, $1,600 flagship camera also will face a new range of full-frame rivals for those willing to pay a significantly higher price. Canon's 5D Mark II, Nikon's D700, and Sony's A850 are relatively elderly, and it will be a surprise if their successors don't feature sensors with compelling, new image quality at their heart.
For those who want to go farther up the product pecking order, Pentax has a different answer than full-frame SLRs, whose sensors are the size of a frame of 35mm film from the the bygone days of analog cameras. Instead, Pentax is selling its medium-format 645D camera, initially in Japan but also in Europe and the United States by the end of the year. Its sensor measures 44x33mm, compared with 36x24mm for full-frame sensors and 23.7x15.7mm for Pentax's K-5. Larger sensors have greater light-gathering abilities, helping in particular in low-light situations, but cost much more to manufacture and require bulkier lenses and camera bodies.