Three midrange Sony SLRs now are included in DxO Labs' measurements of image sensor performance, and the Alpha A700 proves to be reasonably competitive.
Sony's A700, which costs about $1,100 with an 18-70mm lens, has a score of 66.3 on the test, which calculates how well the sensor handles color, a range brightness and darkness, and low-light shooting. That puts it behind the top-scoring camera with a comparably sized sensor, the Nikon D90, almost ties it with the Pentax K10D and Nikon D300, and gives it a a few points' lead over Canon's 40D and 50D.
Meanwhile, the A200 scores 62.9 and the A300 an even 64, according to the DxOMark Sensor test results that were updated Tuesday. A five-point difference makes a difference of about 1/3 stop in exposure, DxO says, meaning that a higher-scoring camera can attain the same raw image quality as a rival even though the higher-scoring camera is using a faster exposure or higher ISO.
DxO Labs, a French company, makes a business of measuring camera image quality, developing technology for image-processing hardware and software, and selling software to convert the raw files produced by higher-end cameras into less flexible but more convenient formats such as JPEG. The DxOMark score measures sensor performance based on the raw file, a foundation for overall image quality but only a facet of a camera's overall performance. … Read more