Loveforever的部落格

Almost exactly two years after the D80 was announced comes its replacement, the rather predictably named D90. The D80 has been one of Nikon's quiet successes, and even today, despite being positively Methuselah-like in digital camera terms it continues to sell and often makes its way into our top 10 most clicked on cameras. Because Nikon d90 battery, looks so similar to the D80 the D90 appears at first glance to be one of those rather subdued incremental upgrades, but dig a little deeper and you'll find there's plenty to keep Nikon fans happy.

First and foremost there's a new CMOS sensor, which Nikon claim produces D300 quality output at up to ISO 6400 and - one of several features to 'trickle down' from higher models - the same highly acclaimed 3.0-inch VGA screen as the D3/D300. Naturally it has Live View with contrast-detect AF and it would have been surprising had it not sported some form of dust removal system. More surprising is the inclusion of the world's first DSLR movie mode (720p HDTV quality, no less) and HDMI output, though as we'll see later it does come with some limitations. A lot of the core photographic spec is the same as or very similar to the Nikon d90 battery,, though there is a new shutter and an implementation of the 3D tracking AF seen on the D3/D300.

And it's not just the high end models that have lent features and technology to the D90; the user interface has been given the same user-friendly treatment as the D60, as have the retouching options. As it was explained to us the D90 is intended to appeal to the broadest audience of any Nikon SLR, from first-time 'step up' customers moving from a compact to serious amateurs wanting comprehensive photographic control without the cost and weight of a D300. Whether the D90 is as capable as its feature set suggests, we'll see as the review unfolds.

Nikon D90 Key Features

• 12.9 megapixel DX-format CMOS sensor (effective pixels: 12.3 million)
• 3.0-inch 920,000 pixel (VGA x 3 colors) TFT-LCD (same as D3 and D300)
• Live View with contrast-detect AF, face detection
• Image sensor cleaning (sensor shake)
• Illuminated focus points
• Movie capture at up to 1280 x 720 (720p) 24 fps with mono sound
• IS0 200-3200 range (100-6400 expanded)
• 4.5 frames per second continuous shooting (buffer: 7 RAW, 25 JPEG fine, 100 JPEG Normal)
• Expeed image processing engine
• 3D tracking AF (11 point)
• Short startup time, viewfinder blackout and shutter lag
• Slightly improved viewfinder (96% frame coverage)
• Extensive in-camera retouching including raw development and straightening
• Improved user interface
• New optional compact GPS unit (fits on hot shoe)
• Same battery and vertical grip as Nikon d90 battery,
• Vignetting control in-camera
• 72 thumbnail and calendar view in playback

Although it has many similarities to its predecessor, the D90 adds a number of new features including some from Nikon's professional DLSRs, and others that are currently unique. The sensor is upgraded to a newly-designed 23.6 x 15.8mm DX format CMOS sensor with a resolution of 12.3 megapixels and built-in sensor cleaning, the LCD monitor is the same incredibly sharp 3.0-inch, 920k unit from the D3 and D300, and it has a new viewfinder with 96 percent frame coverage.

As you're probably aware if you've read this far, the D90's main claim to fame is that it is the world's first digital SLR to feature video shooting capability, in high-definition 1280 x 720 pixel resolution at 24 frames a second with mono audio. However this isn't the D90's only unique feature, beacuse it also has GPS location logging via an optional external satellite receiver which slots onto the flash hot-shoe. I'm hoping to take a look at this gadget when it is launched next week.

While its movie mode certainly ranks as the D90's most novel capability compared with its peers, the implementation leaves quite a bit to be desired. Its movie-capture specifications aren't too shabby: 24 frames per second 1,280x720-pixel motion JPEG and support for VR optical image-stabilization if the lens has it. But it seems like Nikon d90 battery, faced some technical limitations that impair the capture experience, as well as makes some rookie mistakes with both its video and HDMI output. For instance, exposure is fixed for the length of the clip, it has monaural sound, and you can only focus manually while shooting. HD clips are capped at 5 minutes because of file-system limitations. Plus, Nikon doesn't seem to have put sufficient video processing smarts into the camera to properly render video or stills; when connected via the mini-HDMI output, it relies on the TV to do the downconversion to HD resolution for stills (never a good idea) and Nikon's true 24fps video doesn't quite match that of most TV processors' expected 23.976fps, which can result it occasional playback stutter. Still, this has been a long-awaited feature in the entry-level segment, since it's one of the two important most features users have had to sacrifice when moving up to dSLRs (the other being pocketability).

Like the newer Canon EOS 50D, the D90 adds face detection to its Live View repertoire--part of the enhancements enabled by a revision of its Expeed image processor--though it maxes out at five faces. The FD supplies data to the camera's face-priority AF, and Nikon has integrated the FD information into its automatic scene recognition algorithms to help with metering and AF. In practice, it doesn't seem to make much difference, either in speed or portrait quality, over wide-area AF; both of those two AF modes are significantly faster than normal area AF in Live View, however.

There are also the usual array of improvements and additions to shooting controls, including an expansion of Active D-Lighting parameters (you can now go extra high), nine slots for custom Picture Control settings, which can be uploaded to Nikon's Capture NX 2 raw-processing software, as well as advanced scene modes that incorporate Picture Controls and Active D-Lighting, and that can automatically program shift to slower shutter speeds when the camera knows a VR lens is attached. Most important, my casual testing confirmed that operating in Active D-Lighting mode doesn't impose a performance penalty, as can happen because of the processing overhead. The Nikon d90 battery, also includes a socket for Nikon's GP-1 hot shoe GPS device. But I'd trade all these bells and whistles for the custom settings banks found in the D300 and D3, or even a less complex implementation like the three mode-dial-based custom settings slots in the 40D. To get a real sense of any camera's capabilities, I always suggest reading the manual.