I was even more surprised to see that when I ran the Nikon D90 against the Nikon D3100, the D90 kicked the D3100's butt by a significant margin at HIGH ISO. This morning I see 1001 Noisy Cameras has done a similar comparison stacking up the Nikon D3100 against the Nikon D5000, Nikon D90, Nikon D3000, and Nikon D300s.
The DXOMark test results surprised me as it isn't what I've been seeing from my tests. Thom Hogan has also said that from his testing, the D3100 "seems to beat the old 12mp sensor cameras in my low light tests (but only by a small amount)."
So what is going on here?
Why are mine and Thom's initial findings on the Nikon D3100 not jiving with the DXOMark sensor evaluation?
Could it be software related? I don't think so as I've been processing both D90 and D3100 photos I've been using for comparison in Nikon ViewNX2.
I'm drawing a blank at the moment for other possible reasons. Thought about bit depth, but that shouldn't be a factor. Thought about noise reduction, but again, not a factor as shot in RAW and processed with the same software.
The good news is that the Nikon D90 is holding it's own very nicely.
The bad news is that these aren't the same observations I've seen when shooting my Nikon D3100 against the Nikon D90.
I'm hoping Thom will comment on this as he's sure to see the DXOMark results and be questioning them as well.