The D40 is Nikon's smallest and lightest DSLR camera yet - and also the easiest to operate. Designed for everyday photographers, it replaces the D50 model and features the same 6.1-megapixel imager but sports a larger 2.5-inch high-resolution colour LCD monitor. Nikon gives users the choice of three information displays: the classic style found on all Nikon cameras, a new graphic style that shows users the effect of changing controls like lens apertures and a 'wallpaper' style that lets owners upload one of their own shots as a background to the data display.
Interestingly, this is the first Nikon DSLR body without an AF motor; the D40 only supports autofocusing with AF-S and AF-I CPU lenses that have their own built-in motors. It's all part of the simplification process that has made this camera small, light and easy for novices to use. Like the D50, it uses SD cards for image storage but the D40 is SDHC compatible. Another 'less-is-more' strategy is the new, ultra-compact lithium-ion battery.
The camera's plastic body is well-built but a bit small for anybody with large hands, although most controls are easy to access. Top panel controls are clustered on the right side of the camera and consist of a fairly conventional mode dial plus 'info' and exposure compensation buttons. The former calls up the shooting data display. The power switch is a ring around the shutter button. A command dial for adjusting lens apertures, shutter speeds and flash settings (plus other settings selected via Custom functions), lies under the thumb at the top of the rear right side, just next to the AE/AF lock button.
Most of the rear panel is covered by the LCD monitor, which does double duty as a data display. To its left are buttons for accessing the playback, menu, thumbnail display and magnify functions. To the right lie the arrow pad and delete button. On the front panel beside the lens mount are the flash release/flash exposure button (which covers modes and output adjustment) and the self-timer/Function (Fn) button (which can be re-programmed to access drive, image quality/size, ISO or white balance settings). There's no depth-of-field preview button but viewfinder magnification has been increased from 0.75x to 0.8x, which is in line with competing cameras.
The pop-up flash rises high above the lens axis, lifting automatically in the auto shooting mode. With a guide number of 18 (m, ISO 200), it's slightly more powerful than the flash on the D50 and supports i-TTL flash control as well as being compatible with Nikon's Creative Lighting System. A hot shoe is provided for accessory flash units, such as the new, light and ultra-compact SB400 Speedlight, which Nikon has released concurrently with the new camera.
Built into the D40 is a new advanced Nikon Image Processing Engine, which makes the new camera more responsive than its predecessor. However, the Multi-CAM530 autofocus unit only supports three AF areas, whereas the D50's Multi-CAM900 unit supported five. The AF sensors lie linearly across the centre of the viewfinder display with a cross-type sensor in the centre. Algorithms inherited from the D200 and D80 cameras 'drive' autofocusing. Our tests found the D40's system to be fast and accurate, but it had some difficulty locking on to low-contrast subjects in very dim lighting.
The automatic 3D Color Matrix Metering II system is the same as the earlier camera, with a frame-wide 420-pixel sensor that allows the metering system to assess and compare each scene's brightness, contrast and colour with a built-in database covering more than 30,000 real-world lighting scenarios. The camera then determines and sets the correct exposure. Alternative exposure control tools include spot metering, centre-weighted metering and exposure compensation of 5 EV in increments of 1/3 EV. But there's no AE bracketing.
Like Nikon's other enthusiast DSLRs, the D40 provides a choice of three colour space settings: two using sRGB plus Adobe RGB. The default IIIa sRGB setting enhances greens for more colourful mindscape shots, while Ia is recommended for portrait shots. Image quality options include NEF (12-bit compressed raw plus three levels of JPEG compression. There's also a RAW+JPEG setting that records a basic JPEG image with each raw file. Three image sizes are supported: 3008 x 2000 pixels (Large/6MP), 2256 x 1496 pixels (Medium/3.4MP) and 1504 x 1000 pixels (Small/1.5MP).
Sensitivity is adjustable from ISO 200 to 1600, with the auto setting covering the full range. An additional manually selectable HI 1 setting boosts ISO to the equivalent of 3200. Shots taken with HI 1 sensitivity are automatically processed to reduce noise, increasing recording time by about one second per frame. The mode dial carries 12 settings: an auto mode, the standard P, A S and M settings and seven Digital Vari-Program modes: Portrait, Landscape, Child, Sport, Close Up and Night Portrait plus a new Auto (Flash Off) setting to prevent the flash from popping up when you don't want it.
Nine white balance settings are provided, including a 'pre-set' measurement mode. All but the 'pre-set' mode can be fine-tuned in increments of one step across +/- three steps, allowing photographers to 'warm up' or 'cool down' subject colours. Our tests showed this control would be required for most shots taken under artificial lighting. You can also copy white balance from an existing image. Noise reduction processing can be applied to shots taken with high ISO settings but it doubles the image processing time. With the continuous shooting mode, you can record up to 100 JPEG images at 2.5 frames/second but you're limited to four shots when shooting raw files.
Like the D80, the D40's shooting menu contains a range of 'Image Optimisation' settings, including Normal, Softer, Vivid, More vivid, Portrait, Black-and-white and Custom. The effects of these settings are mostly self-explanatory, although the D40's Black-and-white mode only supports colour to monochrome conversion and lacks the colour filters provided in the D80. The Custom setting provides individual adjustments for sharpening, contrast, colour mode/space, saturation and hue; a generous palette for an entry-level DSLR.
In-Camera Processing
Nikon has included several of the built-in editing functions from its compact digicams in the D40 with a special Retouch menu that supports Nikon's D-Lighting exposure balancing, red-eye detection and correction, image trimming, Image Overlay, Small Picture, Monochrome (Black-and-white, Sepia, Cyanotype) and Filter Effects (Skylight, Warm filter, Colour balance). They can be fun to use - and handy under certain circumstances - and may help provide a bridge for anyone who is converting from a digicam to a more sophisticated camera.
The D40 is supplied with Nikon's PictureProject software, which can be used for converting raw files as well as transferring, organising and sharing images via emails, slideshows and albums. We are not enamored with this application and find it over-automated and much less effective than Adobe's Photoshop Elements with Camera Raw. (Purchasers should check Adobe's website to find out when a Camera Raw update with D40 compatibility is released.)
Performance
Pictures taken with the test camera were generally well-exposed, sharp and colour accurate but quite severe coloured fringing was found in outdoor shots in bright conditions, particularly towards the edges of the field of view. Barrel distortion was also observed when the lens was used at the widest setting. However, it was not severe enough to affect general photography.
We achieved some interesting results with our Imatest evaluations. The raw file converter in Imatest dramatically reduced both the contrast and colour saturation of all image files, yielding graphs that appeared to show the D40 was unable to produce colour-accurate pictures. When we used Imatest evaluation on JPEG files, however, test shots taken with the default 'Normal' optimisation setting showed only minor colour drifts in blue through to green hues and a slight boost in saturation in the reds.
Swapping to the other optimisation settings produced further changes, mostly to colour saturation. We've included a graph from the 'More Vivid' setting to show just how much some of these adjustments can affect output quality, especially with respect to saturation and contrast. With the Normal setting, we found saturation was only slightly elevated, much as you would expect in a consumer DSLR.
Imatest also showed the D40 to be capable of producing excellent image resolution. With a lens aperture of f/11 and mid-range focal length - plus ISO 200 sensitivity - we recorded an MTF50 figures of just under 1430 line widths/pixel height, which is excellent for a 6-megapixel camera. There was no evidence of over-processing and image files were generally very clean. Lateral chromatic aberration was also generally low.
The auto white balance had some slight problems correcting colour casts from both incandescent and fluorescent lighting but handled the latter rather better. The manual settings tended to over-correct, producing a distinct blue cast with fluorescent lights and a slight magenta cast with tungsten. The 'pre-set' measurement system delivered very good colour accuracy and is, therefore the best option when shooting in tricky lighting.
Long exposures taken at night yielded some excellent results and little image noise was discernible at ISO settings up to 1600 - unless shots were enlarged substantially. With the HI-1 setting, the automatic noise reduction tended to slightly soften the image but colour noise was obvious when shots were enlarged to full screen size on a PC monitor. The flash required ISO 400 sensitivity to illuminate an average-sized room but spread its light evenly across the field of view of the lens at the 18mm setting.
The test camera powered up almost instantly and shut down within 0.2 seconds. We measured an average capture lag of 0.35 seconds, which reduced to instantaneous capture with pre-focusing. The continuous shooting mode recorded 3.3M JPEG images at 0.35 second intervals for as long as the shutter was held down. NEF RAW files were captured at 0.4 second intervals with a limit of four shots. When RAW+JPEG was selected, the camera took a second to start recording, then captured three shots at 0.35 second intervals. It took 0.7 seconds to clear the buffer memory.
In Summary
The D40 would be a great buy for an amateur photographer who wanted to move up from an advanced digicam to a DSLR or for anyone who wanted to learn more about digital photography. Its graphic display setting and the easy access to text-based help in the camera will give users confidence to try new settings and make it easy for them to improve their picture-taking. Retaining the 6.1-megapixel sensor allows Nikon to offer this camera at a price that is affordable - and competitive.
There is little difference in size and weight between the D40 and many current advanced digicams models but the D40's superior performance puts it well ahead of the lens-integrated models. We made some excellent A3-sized enlargements from shots taken with the D50 and feel this would probably be the limit of enlargement for most potential buyers.
The kit lens is an updated 18-55mm f/3.5-5.6G ED II AF-S DX Zoom-Nikkor lens, which provides 3x optical zoom magnification. It covers angles of view equivalent to 27- 82.5mm in 35mm format and represents a good start-out lens. And Nikon has plenty more lenses to fit on this camera body! For those making their first ventures into digital SLR photography, the D40 could be the start of a satisfying relationship.
IMATEST GRAPHS
The plot from a JPEG image file with the standard optimisation setting.
The plot from a NEF-RAW file showing the de-saturation produced by raw file conversion in Imatest.
The plot from a JPEG file shot with 'More vivid' optimisation.
SAMPLE IMAGES
Auto white balance with fluorescent lighting.
Auto white balance with incandescent lighting.
A crop from an outdoor shot showing coloured fringing near the top corner of the frame.
A crop from a close-up showing the detail and dynamic range the D40 can record.
A portrait shot showing the D40's ability to record skin tones and tonal nuances.
A small area cropped from a long exposure taken with the HI-1 setting shows the softening caused by automatic noise reduction processing but remarkably little image noise.
Image sensor: 23.7 x 15.6 mm RGB CCD with 6.24 million photosites (6.1 megapixels effective)
Lens mount: Nikon F mount with AF coupling and contacts (full support for Type G, D AF Nikkor lenses, AF-S and AF-I lenses)
Focal length crop factor: 1.5x
Image formats: Compressed NEF (RAW): 12-bit compression, JPEG: JPEG baseline compliant (Exif 2.21)
Image Sizes: 3,008 x 2,000 [L], 2,256 x 1,496 [M], 1,504 x 1,000 [S]
Shutter speed range: 30 to 1/4000 seconds in steps of 1/3 plus Bulb
Self-timer: Electronically controlled timer with duration of 2, 5, 10 or 20 s.
Image Stabilisation: n.a.
Dust removal: Anti-dust coating on low pass filter
Exposure Compensation: ±5 EV in increments of 1/3 EV
Focus system: TTL phase detection by Nikon Multi-CAM530 autofocus module with AF-assist (range approximately 0.5-3.0m/1ft. 8in.-9ft. 10in.); Detection range: -1 to +19 EV (ISO 100 at 20°C/68°F)
Focus modes: 1) Autofocus (AF): Instant single-servo AF (AF-S); continuous servo AF (AF-C); auto AF-S/AF-C selection (AF-A); predictive focus tracking automatically activated according to subject status, 2) Manual focus (M)
Exposure metering/control: TTL full-aperture exposure metering system; 1) 3D Color Matrix Metering II (type G and D lenses); Color Matrix Metering II (other CPU lenses); metering performed by 420-segment RGB sensor; 2) Center-weighted: Weight of 75% given to 8mm circle in center of frame; 3) Spot: Meters 3.5mm circle (about 2.5% of frame) centered on active focus area
Custom functions:
ISO range: 200 to 1,600 in steps of 1 EV with additional setting one step over 1600
White balance: Auto (TTL white-balance with 420-pixel RGB sensor), six manual modes with fine-tuning and preset white balance
Flash: 1) TTL: TTL flash control by 420-segment RGB sensor. i-TTL balanced fill-flash for digital SLR and standard i-TTL fill-flash for digital SLR available when CPU lens is used with built-in flash, SB-800, SB-600, and T041, 2) Auto aperture: Available with SB-800 with CPU lens, 3) Non-TTL Auto: Available with Speedlights such as SB-800, 80DX, 28DX, 28, 27, and 22s , 4) Range-priority manual available with SB-800
Sequence shooting: Approx. 2.5 frames per second (Approx. 1.7 frames per second with Noise reduction turned on and approx. 1 frame per second with ISO HI 1)
Storage Media: SD memory card, SDHC compliant
Viewfinder: Fixed-eyelevel penta-Dach mirror type; built-in diopter adjustment (-1.7 to +0.5m-1) (95% coverage)
LCD monitor: 2.5-inch 230,000-dot, low-temperature polysilicon TFT LCD with brightness adjustment
PC interface: USB 2.0 (High-speed): Mass Storage and PTP selectable
Power supply: EN-EL9 rechargeable lithium-ion battery (up to 470 shots/charge)
Dimensions (wxhxd): Approx. 126 x 64 x 94mm
Weight: Approx. 475g (without battery, memory card, lens or body cap)