Built for pixel power, not for speed
You've read it here before: Megapixels aren't everything. Now that the 24.5MP Nikon D3X ($8,000, street, body only) has become the third full-frame DSLR to break the 20MP barrier, how well does that simple truth hold up?
Very well indeed.
As we pointed out in our Hands On last month (February 2009), raising the pixel count involves some tradeoffs. Not just for Nikon, but for the other powerhouses in this category, the Canon EOS-1Ds Mark III ($6,550, street, body only) and Sony Alpha 900 ($3,000, street, body only).
Chief among these: burst speed. The D3X captures full-frame images at a rate of 5 frames per second -- not nearly as swift as the 9-fps rate of Nikon's 12.1MP D3. (Both the Canon and Sony also have 5-fps burst rates.) Another compromise is sensitivity. The D3X has a top ISO of 6400, two stops below the astonishing ISO 25,600 of the D3.
But having run the D3X through our battery of tests in the Pop Photo Lab and used it extensively in the field, we think those compromises were worth it. This is an incredible DSLR. Take a look.
The D3X produces truly stunning pictures. Let's start with resolution, the chief benefit of that full-frame 24.5MP Sony-made CMOS sensor. At its lowest standard sensitivity of ISO 100, the D3X captured an off-the-charts Excellent 3180 lines. The only DSLR to beat it: Sony's own Alpha 900, whose 24.6MP sensor tested at 3230 lines. In real-life shooting, you'll barely see the difference.
Color accuracy? Again, Excellent, with the best score of the new full-frame breed.
Noise performance was a little more complicated vis-a-vis the competition. Still, the Nikon did a top-notch job at suppressing noise throughout its expanded ISO 50-6400 range. At midrange and lower ISOs, the Canon EOS-1Ds Mark III and Sony A900 give the D3X a run for its money. But with only a (barely) Moderate noise score at ISO 6400, compared with Unacceptable for the A900 (the Canon's sensitivity tops out at ISO 3200), the Nikon served up the cleanest images when lights were dim.
All together, these scores were enough to earn the D3X an Excellent rating in overall image quality from ISO 50 through ISO 3200 -- a truly astounding range.
Indeed, the fact that the D3X is sensitive down to ISO 50 is a breakthrough for Nikon, whose previous DSLRs bottomed out at ISO 100. (The Canon goes down to ISO 50, too; the Sony, only to ISO 100.) Interesting, though, that the company backed away from the super-high ISOs of the D3 and D300 -- perhaps deciding that the compromise in image quality at those levels just wasn't worth it.
As we've come to expect these days, the D3X can capture RAW images at 14 bits per color. This expands the number of color gradations between the brightest white and darkest blacks, so you should see smoother gradations in your pictures. The natural side effect, however, is larger RAW image files -- make sure your CF card has plenty of room if you shoot with the D3X in 14-bit (rather than 12-bit) mode.