Why You Can Trust CNET Nikon Coolpix S640 review: Nikon Coolpix S640
Nikon Coolpix S640
- More than two decades experience writing about PCs and accessories, and 15 years writing about cameras of all kinds.
The Nikon Coolpix S640's MSRP is $50 more than its linemate, the S570. But that $50 buys you optical image stabilization, some slightly improved shooting performance, and a couple extra shooting options. Otherwise, it's the same simple and stylish camera with a wide-angle lens, 5x zoom, and consistently very good photo quality below ISO 400. The only thing keeping this very good camera from being better is the lack of an HD-quality movie mode. If you're fine with its VGA-only mode, then the S640 is a better-than-basic ultracompact camera.
Nikon Coolpix S640
The Good
The Bad
The Bottom Line
| Key specifications | Nikon Coolpix S640 |
| Price (MSRP) | $249.99 |
| Dimensions (WHD) | 3.6x2.2x0.8 inches |
| Weight (with battery and media) | 4.8 ounces |
| Megapixels, image sensor size, type | 12 megapixels, 1/2.3-inch CCD |
| LCD size, resolution/viewfinder | 2.7-inch LCD, 230K dots/None |
| Lens (zoom, aperture, focal length) | 5x, f2.7-6.6, 28-140mm (35mm equivalent) |
| File format (still/video) | JPEG/Motion JPEG (.AVI) |
| Highest resolution size (still/video) | 4,000x3,000 pixels/ 640x480 at 30fps |
| Image stabilization type | Electronic |
| Battery type, rated life | Lithium ion rechargeable, 270 shots |
Available in pink, red, white, and black versions, the S640 is a slim, lightweight camera that can be easily slipped into a pants pocket or small bag. Its metal body gives it a sturdy, high-end feel. Its lens specifications add to that feel, hitting all the things good to find on an ultracompact camera--28mm-equivalent wide-angle with a maximum aperture of f2.7 and a 5x zoom range. The only disappointment is that when zoomed out, the aperture goes down to f6.6, making low-light shots iffy when the lens is fully extended. (It was a little more acceptable on the S570 since it was cheaper.) You'll also have to be aware of your finger placement when using the flash, as the bulb is located high on the left side and easily blocked.
Its controls are fairly standard and easily learned with little effort. On its top are the power and shutter release buttons with a zoom control around the release. On its back to the right of the bright LCD and below the thumb rest are buttons for changing shooting modes; playing and editing images; accessing photo, video, and system setting menus; and deleting pictures. There's a dial for quickly moving through settings and photos and it acts as a directional pad for navigation and setting exposure, flash, timer, and macro. Again, it's all pretty straightforward. The dial moves a bit freely; however, there are stops you can feel when using it.
The S640 uses a version of Nikon's four-way VR Image Stabilization that includes optical image stabilization. It will also use high ISO settings and shutter speed adjustments along with motion detection to help with handshake and motion blur.
Another nicety about the S640 is that the camera can be charged via a USB cable.
| General shooting options | Nikon Coolpix S640 |
| ISO sensitivity (full resolution) | Auto; 80; 100; 200; 400; 800; 1,600; 3,200; 6,400 |
| White balance | Auto, Manual, Daylight, Incandescent, Fluorescent, Cloudy, Flash |
| Recording modes | Auto, Scene Auto, Scene, Smart Portrait, Subject Tracking, Movie |
| Focus area modes | Face priority, Auto, Manual, Center |
| Metering | Multi, Center-weighted |
| Color effects | Standard, Vivid, Black & White, Sepia, Cyanotype |
| Burst mode shot limit (full resolution) | 10 photos |
There are 15 scene modes with nothing out of the ordinary, as well as Scene Auto Selector--Nikon's automatic scene-recognition mode. Nikon's Smart Portrait System gets its own spot in the shooting-mode menu. Basically, it combines the previously available Blink Warning, Smile Shutter, In-Camera Red Eye Fix, D-Lighting, and Face Priority AF (autofocus) features into one mode and adds a Skin Softening component. This type of mode is available from other manufacturers, but Nikon's implementation is fast, works well, and has a good balance of sharpness and softening. The most control you get is in the Program mode, called Auto on this camera, that gives you settings for white balance, light metering, ISO, color options, and autofocus. There is also a Subject Tracking mode for locking focus on a moving subject so they're in focus when you're ready to shoot, and a basic movie mode--VGA-quality only with no use of the optical zoom.
Though its shooting performance isn't outstanding, it is better than we've come to expect from a Coolpix camera, and it is on par with its competition. It takes one second to power on and shoot. Subsequent shots will leave you waiting an average of 2.4 seconds between them, going to only 2.7 seconds if you use the flash. Its shutter lag in bright lighting conditions is good at 0.4 second; and in dim lighting it's still decent at 0.8 second. The S640 has a full-resolution continuous shooting speed of one frame per second. These are average performance numbers for its class, but it's an improvement for Nikon; they're still not great for moving subjects, though.
Overall, the S640's photo quality is very good. Many cameras in its class suffer a significant dip in quality when they use any sensitivity above ISO 200. The S640 is actually good to ISO 400, though there is some visible noise and increased softness. The camera lets you limit the auto ISO range to either 100-400 or 100-800; thankfully, its auto ISO only uses up to ISO 1,600. If you're in daylight or bright conditions, I recommend locking it down to 100-400. It performs OK up to ISO 800, but there's definitely increased softness and noise and artifacts. The S640 can shoot at full resolution up to and including a sensitivity of ISO 6,400. However, photos from ISO 1,600 up don't look good because of color shifting and yellow blotching as well as a near absence of image detail. While you can, in fact, keep shooting images in low-light conditions, you probably won't be thrilled by the results.
The S640's image colors are not entirely accurate with it pumping reds and blues up a little, but the results are pleasing. Everything turned out nice and bright and reasonably natural looking. Typical of compact cameras, its image highlights tend to blow out, but at least Nikon's D-Lighting system helps bring up shadow detail.
For a 28mm-equivalent wide-angle lens, the S640 has little in the way of barrel distortion and has no discernible pincushion distortion when the lens is fully extended. In high-contrast areas of photos, there is some purple fringing, but the amounts are below average for its class.
The Nikon Coolpix S640 is just a little above a basic point-and-shoot ultracompact. It's not a bad camera, but it doesn't excel in any one or more areas. Its shooting performance is improved over other Coolpix cameras; however, that only puts it in line with the competition. It does take good photos at ISO 200 and below and to some degree ISO 400. Also in its favor is that it's simple to operate and looks and feels good. If you don't want HD-quality movie capture, the S640 is a fine wide-angle, 5x zoom ultracompact.
(Shorter bars indicate better performance)
 | Time to first shot | | Typical shot-to-shot time (flash) | | Typical shot-to-shot time | | Shutter lag (dim) | | Shutter lag (typical) |
(Longer bars indicate better performance)
Find out more about how we test digital cameras.