Shadowblade wrote in post #15122138
Read the testing methodology.
DXO's ISO benchmark defines the ISO rating as the highest ISO at which a sensor can maintain 9 stops of DR, a 30:1 SNR and 18 bits of colour depth.
The Popphoto test measured only noise, after default noise reduction, and without (what does '2.2 noise performance' at ISO 1600 mean anyway?)
Also, DXO's measurements are done using RAW files with no noise reduction or sharpening applied. The Popphoto test you quoted did it test using RAW files with default settings applied - i.e. with software variation, not purely measuring hardware capability.
I am a Popphoto subscriber overall I like the magazine but I've learned to take their noise tests with a large grain of salt, exactly for that reason.
Even when reading Popphoto's tests of other Canon bodies using (virtually) the same 18mp sensors, there are significant differences between noise perfromance - at least by Popphoto's standards.
Like mentioned above, they "measure" noise after opening the RAW file and using the MANUFACTURER'S own NR settings, which pretty much invalidates any kind of noise level comparison between brands and even between same brand models using virtually the same components.
Easy to see this by importing RAW files taken at the same ISOs from let's say the 7D, t2i, and t4i into DPP. If we look at the NR tab, we can see that the default noise reduction differs between these cameras. But Popphoto does not take this into consideration. So there goes level playing field.
This is exactly the reason why the heavily NR'd by default T1i had better noise level results than the then $8K Nikon D3X (and still "beats" most other Canon APS-C bodies too, even though I know from experience, and from other reputable RAW tests, that it's not the case.)
I'm still torn whether I'll keep the T4i that I ordered from Fry's. Right now, after staring at dozens of comparison images - RAW and Jpegs, I'm leaning towards sending it back (haven't received it yet).
Popphoto's T4i test found pretty good noise results, however, when looking at unprocessed RAW files (at DPreview for instance), we can clearly see a tiny but definite step back regarding high iso noise .
Of course Popphoto does not see this because the default NR for T4i RAW files opened in DPP are cranked up compared to older 18mp sensor Canon models (for example, the default luminance NR setting for ISO3200 images are 5 for 7D and T3i but 8 for T4i. The result is similar cleanness on the surface but obviously heavier NR and its detail smudging side effect.)
Oh, and this is exactly why the 60D (which I also used to own and liked it) beat the D7000 in Popphoto's noise tests, even though the unprocessed D7000 RAW files are a tiny bit less noisy (especially shadow noise) than the unprocessed 60D RAW files (see: DPReview)
What's curious though is that Digital Picture review found that the T4i was sharper than any of the other 18mp sensor Canon models... But that's another topic.