Nikon Coolpix S500

Resolution (4.96)
The Nikon Coolpix S500 flaunts 7.1 megapixels on its 1/2.5-inch CCD. To see how effective it is at capturing details, we photographed an industry standard resolution chart and uploaded the images to Imatest software. We photographed the pictures at various exposure settings to make sure we got the sharpest shot possible. Imatest sorted through and analyzed all the images; we are reporting the sharpest of the batch. That image is pictured below and was taken using the lowest ISO setting of 50 with an aperture of f/3.7 and a focal length of 11mm.

Click to view high-resolution image

The edges of the image are soft, especially in the corners, and they are a bit discolored too; what should be black fades to gray on the outskirts of the picture. Imatest output numerical resolution results in terms of line widths per picture height (lw/ph), which describes the number of alternating black and white lines of equal thickness that can fit across a frame without blurring.

The Nikon Coolpix S500 performed very poorly and resolved only 1367 lw/ph horizontally with 3.2 percent oversharpening and 1385 lw/ph vertically with 3.6 percent oversharpening. These numbers are disappointing especially when compared with those from the 6-megapixel Nikon S5 and S6 digital cameras. The S5 resolved 1497 lw/ph horizontally and 1493 lw/ph vertically. The S6 read 1491 lw/ph horizontally and 1390 lw/ph vertically. The 7.1-megapixel Nikon S500 doesn’t have what it takes to make enormous prints, so use caution when enlarging!

Color (7.03)
To see how accurately the Nikon Coolpix S500 depicts colorful subjects we photographed an industry standard color chart made by GretagMacbeth. The chart shows 24 colors from all parts of the spectrum in a tile-like format. After photographing the color chart using the Nikon S500, we uploaded the images to Imatest imaging software and it analyzed the colors. It compared the S500’s colors to those of the original chart and output the following modified chart that shows a comparison. The outer frame of each tile shows the S500’s perceived color. The inner vertical rectangle shows the ideal color from the original chart. The inner square shows the ideal color corrected for luminance.

From this view the colors look decent. For a more precise measure, Imatest output the following color error chart. It shows the Nikon Coolpix S500’s colors as circles and the colors from the original chart as squares.

The yellows and blues have the most error with color #16’s pastel green-yellow turning into a school bus-type yellow. Most other colors aren’t that far off though with a mean color error of 8.53. The saturation is nearly perfect at 101.6 percent. The Nikon S500’s overall color score of 7.03 is an improvement on previous S-series digital cameras that we’ve tested. For instance, the Nikon S5 has a 6.07 color score and oversaturates by 28.3 percent.

White Balance (4.96)
Auto (3.74)
The automatic setting was the most accurate when the flash was fired, but is otherwise to be avoided.


Preset (6.17)
The preset white balance modes were much more reliable than the automatic setting with the exception of the flash preset. The rule of thumb with this camera is to avoid the automatic setting and either set it to the presets or use the manual white balance.

Flash WB - Flash Illumination

Fluorescent WB - Fluorescent Illumination

Shade WB - Shade Illumination

Tungsten WB - Tungsten Illumination

Still Life
Click on the images below to view the full-resolution images.

Still Life Scene
ISO 50	ISO 50
ISO 100	ISO 100
ISO 200	ISO 200
ISO 400	ISO 400
ISO 800	ISO 800
ISO 1600	ISO 1600
ISO 2000	ISO 2000

Noise – Auto ISO (1.59)
With our studio lights turned up to 3000 lux, we set the camera to automatically choose an ISO setting. It selected an odd ISO 247 which produced way too much noise for such nicely lit conditions.

Noise – Manual ISO (5.63)
Keeping the studio lights bright, we photographed the resolution chart at each of the camera’s manual ISO settings from 50 to 2000. The chart below shows the results. On the horizontal axis are the manual ISO settings and on the vertical axis is the percentage of the image that succumbed to noise.

Noise is nice and low at the ISO 50 setting, but it quickly jumps at the next ISO 100 setting. There is a steady climb to ISO 200 and then a slight drop at ISO 400, indicating an automatic high sensitivity noise reduction system that kicks in around there. From ISO 400, the noise increases dramatically until images are thick with noise. At ISO 2000, about 5 percent of the image is speckled with noise. Overall, the Nikon S500 does well below ISO 400, but the higher ISO sensitivities should be avoided when possible.

Low Light (5.41)
We dimmed the lights and put the camera through our low light tests. The first test was done at 60 lux, which is about the amount of light from two soft lamps in an otherwise darkened room; there’s still enough light to read comfortably. At 30 lux, you’d probably start squinting: that is about the amount of light from a single 40-watt bulb. The final 15 and 5 lux tests are very dark and simply show any limitations the image sensor may have in very harsh conditions.

Low Light Tests
60 Lux	30 Lux
15 Lux	5 Lux

The main issue seen in the images above is noise. They were taken using an ISO 1600 setting and no flash, of course, so speckled noise appeared. Colors also suffered in accuracy and saturation: the saturation reached only 65 percent, which makes for very dull speckled pictures in low light.

Trying to avoid high sensitivity and opt for longer exposures is tough with this skinny camera. It can shoot as long as four seconds, but only in the scene modes. And when it shoots longer than one second, it does so at ISO 50. At and below a one-second shutter speed, the camera can use ISO 400. To get to the point: you can either have long exposures or high ISO sensitivity, but you can’t have both.

Dynamic Range (5.35)
We photographed a backlit Stouffer test film designed to show the dynamic range of digital cameras. The strip of film shows a row of rectangles ranging from very bright/transparent to very dark/opaque. This test shows how many exposure values the camera can capture at each of its ISO settings because there is a strong correlation between the two parameters.

The chart below shows the Nikon S500’s manual ISO settings on the horizontal axis and the number of exposure values it captured on the vertical axis.

At the lowest ISO setting, the camera captured nearly eight exposure values, which is quite good for a slim digital camera. The dynamic range drops quickly with each subsequent ISO setting though, with the biggest drop between ISO 400 and 800. The higher ISO sensitivities are laughable; they are completely unusable. At ISO 2000, there is only one exposure value captured – and that’s in an optimal testing environment! If you’re going to photograph anything with ISO 800 and beyond, expect bland pictures without much dynamic range.

Speed/Timing
Startup to First Shot (7.5)
It took the s500 2.5 seconds to extend its lens and take a shot. This isn’t fantastic, but isn’t too bad either.

Shot-to-Shot (9.0)
The burst mode won’t blow anyone away. The awesome sound of a 10 fps camera won’t be heard on this model. In the continuous mode, the S500 shoots only one picture every second. Its somewhat redeeming quality is that it can do this until the card fills to capacity. In the 16-shot burst mode, it snaps 2 fps but the images are at a tiny resolution and they are stitched together into a single 7.1-megapixel image that looks something like a quilt.

Shutter-to-shot (9.0)
Be ready long before the shot. That’s the key with this camera. It takes 0.6 seconds for it to focus. When the focus is locked though, its shutter lag is hardly measurable.

Processing (5.8)
The Nikon S500 takes its good sweet time to process images; it takes 2.1 seconds to process a single full-resolution shot.

Video Performance (2.76)
Bright Indoor Light - 3000 lux
With the lights just as bright as during the color and noise testing, we tested the S500’s movie mode. It is not nearly as good at replicating colors accurately. The mean color error jumped to 22.2, as opposed to the still images’ 8.53 mark. The nearly perfect saturation of the still pictures rocketed in the movie mode: videos showed an average saturation of 127.8 percent. The amount of noise was not impressive either at 0.6 percent of the image. This camera won’t replace your camcorder.


Low Light - 30 lux
With the lights turned low, we recorded a test chart and had Imatest analyze it. The mean color wasn’t nearly as bad as in bright light, but not nearly as good as in still images. The mean color error was 17.8 and saturation was pitiful at 71 percent, similar to results with the still pictures in low light. The amount of noise jumped to 1.76 percent too, a trend also seen in still pictures.

Resolution
The Nikon Coolpix S500 has a top resolution of 640 x 480 pixels with a 30 fps frame rate. This is what most digital cameras offer. Imatest analyzed lots of footage from the camera and determined the resolution in much the same way it does still images. The units of measurement are the same line widths per picture height (lw/ph). The S500 resolved 244 lw/ph horizontally with 22.8 percent undersharpening and 364 lw/ph vertically with 4.1 percent undersharpening. These poor results are unfortunately typical of compact digital cameras. The Pentax Optio W30 read 272 lw/ph horizontally and 358 lw/ph vertically with its identical advertised video resolution.

(100% crops)

Outdoor Motion
When taken out of the enclosed testing lab into the real world, the S500 didn’t look that great. We shot cars and people moving along and the camera had trouble with this. Metering would flicker and change for no apparent reason at all. The focus would shift and attempt to refocus on moving objects, but usually the subjects were faster than the focus - it all proved quite distracting. There was a jerky motion when subjects moved out of the frame. This is another unfortunate commonality in most compact digital cameras’ movie modes. Colors looked decent in the sunny outdoors, but there was lots of noise and there really shouldn’t be much in this setting.