Nikon Coolpix S640 Review
The Nikon Coolpix S640 is on the face of it a rather run-of-the-mill compact camera, with a 12 megapixel sensor, 5x optical zoom lens and 2.7 inch screen. That's not telling the whole story though, as Nikon are claiming that the diminutive S640 is the fastest focusing camera in its class, and even that it's as fast as their D40 DSLR. The S640 offers more DSLR-like features too, including ultra-fast startup time, a white balance system based on Nikon's DSLR technologies, and high ISO 6400 capability at full resolution. The 28-140mm lens is backed up by Nikon's VR image stabilization system, and other key features include an LCD monitor with Clear Color technology, Quick Retouch, D-Lighting, Motion Detection and Subject Tracking. The all-metal Nikon Coolpix S640 is available in black or silver for $249.95 / £239 / €269.
Ease of Use
At first glance the Nikon Coolpix S640 looks pretty much like any other small pocket compact camera, easily fitting in both the palm of your hand and a shirt pocket. The external design is appealing in a conservative kind of way, with the all-plastic body finished in a glossy black coating. There's nothing here to surprise or scare anyone who has used a digital camera in the last five years, making it easy to get up and running in no time at all.
And that's certainly helped by the S640's lightening fast reflexes. As promised by Nikon, this is certainly one speedy compact camera. Start-up time is almost instant, with the camera ready to go in less than half a second. At least, that's partly true, in the sense that the LCD screen springs into life. Annoyingly, you have to wait for a further 5 seconds before you can access the main menu, zoom the lens, or perhaps most importantly, playback or take a picture! Nikon's claims about the ultra-fast start-up are therefore misleading to say the least, so much so that after a while I just left the S640 permanently turned on, so annoying was the wait for it to spark into life.
Thankfully, when the camera has finally woken up, the S640 is something of a speed demon when it comes to focusing on your subject. The 5x zoom lens provides a versatile focal range of 28-140mm, impressive given the overall size of the camera, and is wide enough for landscapes and with enough reach for candid portraits. The lens has a fast maximum aperture of f/2.7 at the wide-angle end but a disappointingly slow f/6.6 at full telephoto.
The Nikon S640 is very quick to find focus, locking onto your target in less than 0.2 seconds, regardless of the lighting conditions or which end of the zoom range you're using. Very impressive given that the S640 is using a contrast AF system, which is traditionally slower than the phase detection system that most DSLR cameras use. In addition, the Subject Tracking mode detects, tracks, and focuses on the main subject, making it easier to capture moving subjects successfully.
Thankfully Nikon have included their VR (Vibration Reduction) image stabilisation system to help prevent camera-shake, an essential feature nowadays, although annoyingly there isn't a dedicated button to turn it on and off (it's buried within the Setup main menu). In practice I found that the VR system makes a noticeable difference to the sharpness of the images, as shown in the examples on the Image Quality page, but don't expect to get sharp results every time at the longer focal lengths without the use of a suitably fast shutter speed. Thankfully leaving the anti-shake system on didn't negatively affect the battery-life, with the camera managing just over 250 shots using the supplied Lithium-ion rechargeable battery.
In addition, there are two other functions that also help to prevent camera shake. High ISO light sensitivity up to ISO 6400 at full resolution throughout the range reduces the risk of blurred images, while the Motion Detection option automatically detects and compensates for both camera and subject movement. Best Shot Selector (BSS) mode automatically selects the sharpest of up to 10 sequential shots. All of these 3 options and the Vibration Reduction system can be used at the same time if so desired.
The 2.7 inch LCD monitor on the back of the camera has a rather average resolution of 230,000 pixels, a little on the low side for such a large screen, resulting in a slightly grainy display. On the plus side it also offers five levels of brightness, an anti-reflection coating, a wide viewing angle, and a special antifouling and water repellent layer. It also features Nikon's Clear Color Display, which promises brighter and more vibrant images, although to be honest we've seen better monitors elsewhere.
There aren't too many external controls and buttons (just 9 in total) on the Coolpix S640, reflecting the fact that this is a point and shoot camera with no manual controls. On top of the camera is the On / Off button, shutter release button and tactile push/pull zoom lever. On the bottom the S640 has an SD compatible memory card slot, allowing the use of either SD or SDHC cards, and there's also 45MB of internal memory, which can store 7 images at the highest quality level. The memory card slot is shared with the battery compartment. There's also a very inconveniently located plastic tripod socket which is almost not worth using.
The rear of the S640 is as traditional as the design of the rest of the camera. All of the controls are located to the right of the LCD screen, with a round navigation wheel and a central OK button, surrounded by two buttons both above and below. The navigation wheel is a nice touch that can be used to scroll through menu settings and pictures, but doesn't really serve any other purpose. The four corners of the wheel also double up to access the flash, exposure compensation, macro and self-timer settings (starting at 12 o'clock and going clockwise).
Above the navigation wheel are buttons for accessing the various scene and movie modes and playing back your images. There are 21 scene modes to choose from, including the clever Scene Auto Selector, which automatically recognizes the scene in your picture from 6 presets (Portrait, Landscape, Night Portrait, Night Landscape, Closeup and Backlight) and adjusts the camera settings accordingly. Below the navigation wheel are the self-explanatory Menu and Delete buttons. Unfortunately there's no quick way to change the ISO speed or other key settings, forcing you to delve into the menu system.
If you have never used a digital camera before, or you're upgrading from a more basic model, reading the well-written and easy-to-follow manual before you start is a good idea. Thankfully Nikon have bucked the recent trend of not providing hard-copy manuals by supplying it in printed format.
D-Lighting is a long-standing Nikon technology that brightens the shadow areas of an image, and on the S640 it can be applied to an image both before and after it has been taken. Face-priority Autofocus can detect up to 12 faces in a scene just so long as they're looking directly at the camera, whilst In-Camera Red-Eye Fix automatically processes the picture to remove red-eye. Blink Warning alerts you if someone in the frame had their eyes closed, and the Smile Timer automatically takes the picture when a smile is detected. The Colour Options allow you to tweak the look and feel of your images before you take them, with 5 presets on offer.
|Memory Card Slot
Movie recording on the Nikon Coolpix S640 is something of a let-down in light of the recent shift to HD quality video. In contrast the S640 only offers 640x480 pixel VGA movies at 30 or 15fps, or 320x240 pixels at 15fps. Even worse, you can't use the optical zoom lens during recording, with just a 2x digital zoom available, and there's only an electronic vibration reduction system.
In the Continuous shooting mode the S640 takes just 0.8 frames per second at the highest image quality, which is well below average for this class of camera. There is also a Multi-shot 16 mode that takes 16 photos at 7.5 frames per second and arranges them into a single image.
The Monitor Settings menu option toggles between various views, including showing detailed settings information about each picture, such as the ISO rating and aperture/shutter speed, framelines and no information. Unfortunately there is no histogram available during composition or playback.
Once you have captured a photo, the Nikon Coolpix S640 has quite a good range of options when it comes to playing, reviewing and managing your images. You can instantly scroll through the images that you have taken, view thumbnails (up to 16 onscreen at the same time), zoom in and out up to 10x magnification, apply D-Lighting, the new Skin Softening feature, and Quick Retouch (improves the contrast and saturation), set the print order, view a slide show, delete, protect, rotate, hide and copy an image, plus create a smaller version and add a black border.
In summary the otherwise unremarkable Nikon Coolpix S640 is one of the fastest and most responsive compact cameras around, marred only by the inexplicable 5 second "freeze" when powered-on.
All of the sample images in this Review were taken using the 12.2 megapixel High JPEG setting, which gives an average image size of around 4Mb.
TheNikon Coolpix S640 produced images of very good quality during the review period. This camera handled noise very well, not becoming obvious until the relatively slow speed of ISO 800 and then becoming progressively worse at the fastest settings of ISO 1600 and 3200 - still, not bad for such a small image sensor. The fastest setting of ISO 6400 is best avoided.
Chromatic aberrations in the form of purple fringing effects only appeared in high contrast situations and were generally well controlled. The 12.2 megapixel images were a little soft straight out of the camera at the default sharpen setting and require some further sharpening in an application like Adobe Photoshop, as you can't change the in-camera sharpening level.
Macro performance is excellent, allowing you to focus as close as 2cms away from the subject. The built-in flash worked well indoors, with little sign of red-eye, although it's not powerful enough to illuminate the entire scene at the wide-angle end of the zoom.
Anti-shake works very well when hand-holding the camera in low-light conditions or when using the telephoto end of the zoom range. The disappointing maximum shutter speed of 4 seconds doesn't allow the camera to capture enough light for most after-dark situations.
There are 7 ISO settings available on the Nikon Coolpix S640. Here are some 100% crops which show the noise levels for each ISO setting.
ISO 100 (100% Crop)
ISO 200 (100% Crop)
ISO 400 (100% Crop)
ISO 800 (100% Crop)
ISO 1600 (100% Crop)
ISO 3200 (100% Crop)
ISO 6400 (100% Crop)
The Nikon Coolpix S640's 5x zoom lens offers a versatile focal range, as illustrated by these examples:
Here are two 100% crops which have been Saved as Web - Quality 50 in Photoshop. The right-hand image has had some sharpening applied in Photoshop. The out-of-the camera images are a little soft at the default sharpening setting. You can't change the in-camera sharpening level if you don't like the default look.
Original (100% Crop)
Sharpened (100% Crop)
The Nikon Coolpix S640 has 2 different image quality settings available, with High being the highest quality option. Here are some 100% crops which show the quality of the various options, with the file size shown in brackets.
12M High (3.95Mb) (100% Crop)
12M Normal (2.36Mb) (100% Crop)
The Nikon Coolpix S640 handled chromatic aberrations quite well during the review, with fairly limited purple fringing present around the edges of objects in high-contrast situations, as shown in the examples below.
Example 1 (100% Crop)
Example 2 (100% Crop)
The Nikon Coolpix S640 allows you to focus on a subject that is 2cms away from the camera. The first image shows how close you can get to the subject (in this case a compact flash card). The second image is a 100% crop.
The flash settings on the Nikon Coolpix S640 are Auto, Flash On, Red-eye Reduction, Slow Synchro and Off. These shots of a white coloured wall were taken at a distance of 1.5m.
Flash Off - Wide Angle (28mm)
Flash On - Wide Angle (28mm)
Flash Off - Telephoto (140mm)
Flash On - Telephoto (140mm)
And here are some portrait shots. As you can see, neither the Flash On or the Red-eye-Reduction settings caused any red-eye.
|Flash On (100% Crop)
Red-eye Reduction (100% Crop)
The Nikon Coolpix S640's maximum shutter speed is 4 seconds, which is not very good news if you're seriously interested in night photography. The shot below was taken using a shutter speed of 1 second at ISO 400. I've included a 100% crop of the image to show what the quality is like.
Night Shot (100% Crop)
The Nikon Coolpix S640 has an anti-shake mechanism, which allows you to take sharp photos at slower shutter speeds than other digital cameras. To test this, I took 2 handheld shots of the same subject with the same settings. The first shot was taken with anti shake turned off, the second with it turned on. Here are some 100% crops of the images to show the results. As you can see, with anti shake turned on, the images are much sharper than with anti shake turned off. This feature really does seem to make a difference and could mean capturing a successful, sharp shot or missing the opportunity altogether.
Shutter Speed / Focal Length
Anti Shake Off (100% Crop)
Anti Shake On (100% Crop)
|1/6th / 28mm
|0.77 sec / 140mm
This is a selection of sample images from the Nikon Coolpix S640 camera, which were all taken using the 12.2 megapixel High JPEG setting. The thumbnails below link to the full-sized versions, which have not been altered in any way.
Sample Movie & Video
Front of the Camera
Front of the Camera / Lens Extended
Rear of the Camera
Rear of the Camera / Image Displayed
Rear of the Camera / Turned On
Rear of the Camera / Main Menu
Top of the Camera
Bottom of the Camera
|Side of the Camera
|Side of the Camera
|Front of the Camera
|Front of the Camera
|Memory Card Slot
The Nikon Coolpix S640 is one of the fastest compact cameras currently on the market, quickly starting up and finding focus in good light and bad. An inexplicable 5 second delay after the S640 is powered on and a rather average feature set detract from an otherwise accomplished camera.
Nikon are pushing the speed of the S640, and it certainly doesn't disappoint in this regard. Focusing is on a par with most entry-level DSLRs, quickly locking onto the subject without too many misses. The S640 also bursts into life very quickly, although it's best to leave the camera turned on to avoid that puzzling 5 second "freeze". Other features are a little more mundane, with the versatile 5x optical zoom the pick of the bunch.
Image quality is very good, with more than acceptable results in terms of noise from ISO 100-800, although the faster settings of 3200 and 6400 aren't worth using. Chromatic aberrations are well-controlled, the 2cm macro is very useful, as is the built-in anti-shake system. Only a slightly under-powered flash and disappointing maximum shutter speed of 4 seconds spoil an otherwise appealing performance.
In summary, the Nikon Coolpix S640 is a simple-to-use point-and-shoot compact that won't leave you hanging around, being fast and clever enough to take sharp pictures of both static and moving subjects - exactly what most family snappers want from a camera.
|Ratings (out of 5)
|Value for money
Reviews of the Nikon Coolpix S640 from around the web.
The Nikon Coolpix S640 is a very small ultra-compact camera with a stabilized wide-angle lens, offering a 4X range from 28 to 112mm, in 35mm-equivalent terms. Up to relatively recently, there was very little competition in terms of wide-angle ultra-compact digital cameras. This is no longer the case, putting the S640 face-to-face with more competitors than ever.
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1/2.33-in. CCD; total pixels: approx. 12.39 million
5x zoom NIKKOR; 5.0-25.0mm (equivalent with 35mm  format picture angle: 28-140mm); f/2.7-6.6; Digital zoom: up to 4x (35mm  format picture angle: 560mm)
45cm (1 ft. 6 in.) to infinity (∞), Macro mode: 2cm (0.8 in.) to infinity (∞)
2.7-in., approx. 230k-dot, wide-viewing angle TFT LCD with anti-reflection coating, antifouling and water repellent layer
Internal memory (approx. 45 MB), SD/SDHC memory cards*
* Not compatible with Multi Media Cards (MMC).
4000 x 3000 (High: 4000?/Normal: 4000), 3264 x 2448 (Normal: 3264), 2592 x 1944 (Normal: 2592), 2048 x 1536 (Normal: 2048), 1024 x 768 (PC: 1024), 640 x 480 (TV: 640), 3968 x 2232 (16:9: 3968)
Lens shift VR
ISO 100, 200, 400, 800, 1600, 3200, 6400, Auto (auto gain ISO 100-1600), Fixed range auto (ISO 100-400, 100-800)
Rechargeable Li-ion Battery EN-EL12 (supplied), Charging AC Adapter EH-68P/EH-68P (AR) (supplied), AC Adapter EH-62F (optional), Battery Charger MH-65 (optional)
Approx. 270 shots with EN-EL12 battery
Approx. 91 x 55 x 20.5 mm (3.6 x 2.2 x 0.8 in.) excluding projections
Approx. 110 g (3.9 oz.) without battery and SD/SDHC memory card
Rechargeable Li-ion Battery EN-EL12, Charging AC Adapter EH-68P, USB Cable UC-E6, Audio Video Cable EG-CP14, Strap AN-CP19, Software Suite CD-ROM
* Supplied accessories may differ by country or area.
AC Adapter EH-62F, Battery Charger MH-65