Sony Alpha A700

Outdoor Day Crops

For these daylight photography crops, the Sony Alpha A700 is compared to the Pentax K10D. These shot are designed to compare how cameras behave when faced with typical outdoor conditions. Besides setting the ISO sensitivity, selecting aperture-priority mode at F8 and mounting the cameras on a tripod, everything else is left on automatic.The Sony 16-105 F3.5-5.6 lens was used on the Sony and the Sigma 24-135 F2.8-4.5 was used on the Pentax. In this case, the results are very interesting.

The most striking difference between the first row of crops are the colors. The Pentax clearly shows deeper colors, particularly the sky's blue. Upon close inspection, the difference is more due to brightness than to hue. However, the Pentax's automatic white-balance did choose a more bluish rendition for this scene. There is also a significant difference in brightness which is rather interesting because both cameras metered the same exposure: 1/90s and F8, in the case of ISO 100. Since the sensitivity, shutter-speed and aperture are all identical, differences cannot be explained by metering. The most plausible explanation is that the A700 and K10D have different internal contrast curves because of differences in dynamic range. Basically, to pack two different dynamic ranges in the same JPEG bit-depth, different contrast curves must be used. For the record, the sky's color was somewhere between the two at the time of the shoot, but closer to the Pentax since it was early morning.

In terms of image-noise, the Sony Alpha A700 shows its lead over the K10D as early as ISO 200. While both ISO 200 shots are great, the Sony's is silky smooth. Differences in noise gradually become more noticeable from ISO 400 onward. By ISO 1600, which is the K10D's maximum sensitivity, the A700 has nearly an advantage of nearly one stop. In the ISO 6400 crop, the Sony's maximum sensitivity, noise is clearly apparent, but no more than the K10D's ISO 1600 crop. This is an excellent performance considering the Alpha A700 also has 20% more pixels. Even relatively large prints we possible with the A700 up to ISO 1600. From the ISO 3200 and 6400 shots, we also managed some good-looking medium size prints (8"x12"). This type of quality for relatively bright scenes is quite impressive. Although the A700 performs well in low-light too, our slow-shutter photographs were too noisy for medium prints at ISO 3200 and 6400.

Sony Alpha A700 Pentax K10D
baselong