Color (8.55)
All cameras reproduce colors differently. Some oversaturate colors, making them more vivid but also less natural, while others undersaturate colors, making them more subtle but also dull. Ideally cameras will reproduce colors as accurately as possible. We test color accuracy by photographing a GretagMacbeth ColorChecker test chart and comparing the colors the camera reproduces with the ideal colors of the test chart. The ColorChecker chart is made of 24 different color tiles, representing a broad sample of commonly photographed colors. The image below shows how the Nikon S700’s colors match up to ideal colors of the ColorChecker. The outside squares show the colors the S700 reproduces, the inside squares show the ideal colors of the test chart corrected for exposure, and the small inner rectangles show the ideal chart colors under a perfectly even exposure.
Notice how a number of the outer squares blend right into the inner squares. This indicates great color accuracy, with the exception of some of the yellow and blue tiles. The graph below shows color accuracy in a more quantitative way. The background shows the entire color spectrum, while the ideal chart colors are shown as squares and the S700’s colors are shown as circles. The lines connecting the squares and circles show the amount of color error for each tile.
The graph confirms that many of the colors are spot on, except for vivid yellows, greens, and blues. These colors are significantly undersaturated, meaning bright colors in your photographs will not pop nearly as much as they could. Overall, the S700 has a mean saturation of 92 percent, which is more undersaturated than most cameras we have seen this year. The S700 reproduces hues quite accurately, but the undersaturation makes them look flat.
Resolution (8.32)
Nikon catches up in the point-and-shoot megapixel race with the 12-megapixel Coolpix S700 and P5100, part of its latest batch of cameras. High megapixel counts often improve resolution, but at the cost of other image quality factors, such as noise levels and dynamic range. We test resolution by photographing an industry standard resolution test chart at varied focal lengths and exposure settings. We then run the photos through Imatest, which measures resolution in terms of line widths per picture height (lw/ph), which represent the number of equally spaced, alternating black and white lines that can fit across the image frame before becoming blurred.
The S700 proved to be sharpest at ISO 64, f/4.3, and a focal length of 16mm. At these settings, the camera resolved 1912 lw/ph horizontally with 2.9 percent oversharpening, and 1848 lw/ph vertically with 3.6 percent undersharpening. These numbers are impressive, and show that the S700 can produce sharp images without oversharpening them significantly with the processor. The images also stay very sharp across the entire frame, with only faint blurring and color fringing on the edges. Overall, the 12-megapixel S700 scores very well on resolution performance, much better than the 8-megapixel S510. Keep this in mind if you plan to make large prints.
Noise – Manual ISO (5.81)
Image “noise” refers to the ugly grainy or splotchy quality digital photos can sometimes have, especially at high ISO speeds. Cameras with high megapixel counts generally have more noise because the pixels are smaller, so they can fit on the sensor. Smaller pixels characteristically have a worse signal to noise ratio than larger pixels. We test noise levels by photographing our test chart under bright, even studio lights at all ISO speeds available on the camera. We run the images through Imatest, which determines noise levels by the percentage of image detail the noise drowns out.
The S700 keeps noise levels very low up to ISO 800, but only with the help of significant noise reduction smoothing. This smoothing is evident at all ISO speeds, but becomes worse at ISO 400 and 800. By smoothing over noise, the camera also smoothes over fine image detail, showing the tradeoff between low noise levels and lots of noise smoothing. The noise levels are incredibly high at ISO 1600 and 2000, suggesting that images shot at low ISO speeds would also have high noise levels without the smoothing noise reduction. ISO 1600 and 2000 have so much grainy noise that they are essentially unusable. Despite this, the S700 still controls noise better than the Coolpix S510.
Noise – Auto ISO (1.61)
We also test noise levels with cameras set to Auto ISO, under the same bright studio lights as above. The camera chose an odd ISO 329, according to its EXIF data, and had a fair amount of noise. To keep noise levels as low as possible, manually set this camera to low ISO speeds.
Still Life Sequences
Click to view the high resolution images
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Still Life Scene
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ISO 64
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ISO 64
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ISO 100
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ISO 100
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ISO 200
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ISO 200
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ISO 400
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ISO 400
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ISO 800
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ISO 800
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ISO 1600
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ISO 1600
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ISO 2000
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ISO 2000
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White Balance (8.45)
Good color accuracy means very little if a camera can’t properly white balance. Each type of light source has a different color cast to it, and cameras must be able to adjust accordingly. We test white balance by photographing the ColorChecker test chart under four different types of light: flash, fluorescent, outdoor shade, and tungsten. We test the Auto white balance setting as well as the appropriate white balance presets.
Auto (6.76)
The S700’s Auto white balance is very accurate using the flash, mediocre under outdoor shade, but poor under fluorescent and tungsten light. The images below show the color casts that your images will take on in the various light conditions.
Auto WB - Flash Illumination
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Auto WB - Fluorescent Illumination
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Auto WB - Shade Illumination
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Auto WB - Tungsten Illumination
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Preset (10.14)
The S700’s white balance is significantly more accurate when using the white balance presets. The S700 is very accurate under tungsten and white fluorescent light, and mediocre under outdoor shade (using the Cloudy setting) and when using the flash. Interestingly, the white balance is more accurate under the flash in the Auto setting than the Flash preset. Yet overall, the presets are more accurate than the Auto setting in this camera, especially when shooting indoors.
Flash WB - Flash Illumination
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Fluorescent WB - Fluorescent Illumination
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Shade WB - Shade Illumination
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Tungsten WB - Tungsten Illumination
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Low Light (5.86)
In addition to testing color accuracy and noise levels in bright light, we test how cameras perform in less-than-ideal shooting conditions. We test camera performance in low light by photographing the ColorChecker chart at light levels of 60, 30, 15, and 5 lux. 60 lux is as bright at a room lit softly by two table lamps, 30 lux approximates the brightness of a room lit only by a 40 watt bulb, 30 lux is about as bright as a room lit by a large television screen, and 5 lux is quite dark and tests the limit of the sensor. All shots are taken at ISO 1600.
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Low Light Tests
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60 Lux
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30 Lux
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15 Lux
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5 Lux
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The S700 can just barely expose at 5 lux, showing that it has a limit in low light, but should be able to expose in most shooting situations. However, noise levels are incredibly high in low light at ISO 1600, making images look like they were taken in a blizzard. The high noise levels obscure the images so much that color accuracy is degraded as well. This is not a terrific camera for low light shooting.
We also test long exposure performance with cameras set to ISO 400. The S700 can slow its shutter to 4 seconds in Night Landscape mode (which lacks manual ISO control), and can only take exposures as long as 1 second in normal Shooting mode. The 1 second exposure at ISO 400 had fairly low noise, but also some significant color error. There isn’t much room to experiment with long exposures on the Nikon S700.
Dynamic Range (5.55)
Dynamic range is an important aspect of image quality. In tells how well a camera can capture detail in photos with high contrast. A camera with good dynamic range can show detail in bright highlights and dark shadows in the same photograph. We test dynamic range by photographing a backlit Stouffer step chart at every ISO speed a camera offers. The Stouffer chart is made of a long row of small rectangles, each a slightly different shade of gray, arranged from brightest white to darkest black. The more rectangles a camera can discern, the better its dynamic range.
The Nikon S700 has excellent dynamic range at ISO 64 and 100, but then falls off at higher ISO speeds. At ISO 1600 and 2000, dynamic range is so poor that images will be barely useable. Dynamic range is closely associated with noise levels, and you can see how this dynamic range graph mirrors the noise graph further up the page, only inverted. Overall, the S700 has pretty average dynamic range, scoring slightly better than the Nikon S510.
Speed/Timing – All speed tests were conducted using a Kingston Ultimate 120X 2GB SD Card, with the camera set to highest resolution and best quality, unless otherwise noted.
Startup to First Shot (7.2)
The S700 takes 2.8 seconds to turn on and take its first shot. This is about a second slower than the lower-priced Nikon S510.
Shot-to-Shot (8.7)
The Nikon S700 has several multi-shot modes, including Continuous, BSS, Multi-shot 16, and Interval Timer Shooting. In Continuous mode, the camera takes 3 shots approximately 1.3 seconds apart, and then slows to a shot every 3 seconds. This isn’t fast enough to capture many good sports action shots. In BSS mode, the S700 takes 10 shots in 10 seconds, but only saves the sharpest one. In Multi-shot 16 mode, the camera takes 16 shots, each 1 second apart, and stitches them into one full-sized collage. This is a fun mode to play around with, but not too practical.
Shutter-to-Shot (9.0)
The S700 has no measurable lag when the shutter is held halfway down and prefocused, but a lag of 0.3 seconds when it is not prefocused.
Processing (5.4)
The camera takes approximately 2.3 seconds to process one 4 MB full resolution best quality photo taken at ISO 174 (according to the EXIF data).
Video Performance (3.09)
Bright Indoor Light – 3000 lux
We capture footage of our color charts under bright studio lights to see how cameras render color in Movie mode. The S700 has good color accuracy for tungsten studio lights, but has a bit more noise than we usually see in such bright light. This noise is visible in the video.
Low Light – 30 lux
In low light, the S700 has far worse color accuracy and high amounts of noise. The camera can’t expose video properly at 30 lux, showing that it has clear limits in low light. This isn’t a camera for shooting video of your friends at a club, or your family at sunset.
Resolution
We also record footage of our resolution test chart to see how sharp cameras are in Movie mode. The S700 recorded 263 lw/ph horizontally with 18.4 percent undersharpening, and 285 lw/ph vertically with 11.5 percent undersharpening. These are decent numbers, but the footage still shows ugly jagged edges from the video compression.
Outdoor Motion
We take cameras outside to capture moving cars and pedestrians on the street. The S700’s video looks very similar to the S510’s; good-looking exposure, but substantial moiré, visible noise, stuttering as objects move off the frame, and rather dull colors. Overall, the video looks decent for a digital camera, but doesn’t look as good as the similarly-priced Canon SD870 IS, for example.
