Sony Cyber-shot DSC-T700

Noise
Image noise is the insidious appearance of grain-like imperfections that occur in digital photographs, especially at high ISOs. You'll notice it most across areas of solid color, like the sky, or solid-painted walls. We tested the T700's noise levels by shooting the standard Gretag Macbeth color chart at every available manual ISO level as well as the camera's auto ISO mode to see measure the percentage of noise in the resulting images.

Noise – Manual ISO (10.58)
The graph below shows the noise levels at every ISO from 80 to 3200. This upward trend is normal, as the higher ISOs are more noise-prone. The T700 fared well in this test, only passing 2% noise at ISO 3200. This demonstrates the camera's ability to keep noise levels down while shooting in a well-lit environment.

This overall good performance while manually setting the ISO gives the DSC-T700 an excellent score for a point-and-shoot camera. The noise levels are low across the entire run of well-lit photographs.

Auto Noise (1.71)
Unfortunately, the T700's excellent manual noise score wasn't equaled in the auto noise test. In this second round of noise testing, we grill the camera's intelligence at choosing an appropriately low ISO under well-lit conditions. Unfortunately, the T700 proved to be as dumb as it is pretty. Even shooting under bright studio lights,  the camera deigned to set itself to ISO 400, higher than it needed to be, and resulted in a low auto noise score. This is hardly unusual, as many cameras seem to struggle with correctly gauging which ISO to use in the situation.

Low Light (3.84)
Usually, we test a camera's low light abilities in two ways, first by checking its color accuracy under decreasing light levels, then by putting it through its paces for long exposure settings. Unfortunately, with the T700, we were unable to undertake the second set of tests, because of its inability to shoot at exposure times of one second or greater. This is clearly not a camera to capture late-night shenanigans, at least without a flash.

With the low light test we were able to run, we shot the standard Gretag Macbeth chart under 60 lux (the brightness of a room lit by two small lamps), 30 lux (equivalent to a single 40 watt bulb), 15 lux (the light provided by a television screen) and 5 lux (about a single candle in a dark room), at ISO 1600. The T700 seems to really struggle in low light conditions, scoring poorly in this test. Even at 60 lux, it had low color accuracy and high noise, which was disappointing considering its excellent score for noise under good lighting conditions. This stylish camera would look right in a trendy night club or bar, but low-light candids would be a definite problem.

Sony DSC-T700 Low Light Scores

Still Life
In order to give you a better idea of how the different ISOs actually effect picture quality, we've taken a series of images at all the different settings, shown below. You can click on any image to see the full size version, but be aware that they're big, and may take quite a while to download.

Video Performance (6.94)
The Cyber-shot DSC-T700 has a video mode that can shoot at both 320 x 240 (8.3 fps) and 640 x 480 (30 fps and 16.6 fps), and we run our tests at the highest quality available. We test color accuracy in both bright and low light, and the resolution of the video captured. 8.3 fps is on the very low end, so while you're videos won't take up much space, they'll be incredibly jerky and stilted.

Bright Indoor Light - 3000 Lux
Our first test involves lighting the Gretag Macbeth color chart about the brightness of indirect sunlight. We then record a video of this, export still frames from the video file, and run them through Imatest to analyze the color accuracy. As you can see, the T700 did relatively well, and recorded most of the colors quite close to their original value. There was a bit of trouble with the yellows and oranges, but the blues and greens held up nicely.