Pixel peepers will ALWAYS tear apart anyone's attempt at doing a comp test if their body of the week comes up short, but the test in question was well done.
Measuring MTF charts, etc is all well and good, but this is more akin to what one of us might do (but better and more methodical) when we get a new body. The layout also makes comparisions easier.
The translation isn't perfect (CA in Spanish..;>), but more than adequate to understand exactly what is being stated
My take:
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D300 and 40D nice and about on par until 800. From what I've seen and played with, I'd agree, especially if you try and recover shadows from the 40D at 800.
If you shoot under 800 and don't mind 800 with a touch of NR (they are 12Mp on a 1.5-1.6 crop sensor afterall) and like a crop - you really couldn't go wrong (IQ wise) with either. Some firmware weirdness at 'simulated' low ISO settings, but such is life. Hell of a step up for the D200 IMHO. Feature-set wise (not in the review) - the D300- wins easily.
D2X we all know about - tests just confirmed where it sat noise-wise.
D3 will be /is a barn burner - the illegitimate child of a 5D and 1D3 as it were . Hell of an achievement and long overdue from Nikon. It is the white glove across Canon's face. Lets see the response.
This one camera could do more for ALL shooters in terms of prices and bang for the buck than any in recent history. Canon has to seriously "get on the stick" - it can no longer rest on it's low-noise gold standard laurels.
Of the bodies tested, 5D, IQ-wise, is hand in hand with the D3, maybe a tad better (on screen anyway) until you get into the ultra-high settings allowed by the D3.
Makes sense in that as much as Nikon is playing catch-up on sensor tech to Canon, they have the benefit vs. the 5D of having a sensor that is 2 yrs more advanced.
Personally I cam from Nikon to Canon and shoot Leica lenses and couldn't give a rat's tuckus what name is on my camera - only what comes out of it's sesnor and the glass in front of it.
As such, if the D3 stays out of trouble during the next 12 mos or so, I'd consider a move for the ergos, CLS, in-camera manual lens EXIF database, AF micro-adjust and IMHO the nicer glass Nikon has recently delivered as well as the ability to use Zeiss ZF without step-down.
THE most important thing from the D3/D300? We have FINALLY have the two biggest competitors on levelish footing IQ wise at real worlds ISO usage levels (ISO 25,600? Buy NV googles for @#$ sake...) so we can now start focusing more on handling, features and glass.
Ah, just like the old days ;>
Nicely done.