I remember when the T3/1100D was first announced, several people were wondering if its 12MP sensor was the same as the one in the XSi/450D. The Digital Picture now has his standard comparison chart up and I'm wondering what it shows.
What I see on the colour patch target is that the noise levels on the 450D & 1100D look pretty much identical up to ISO200, with a marginal improvement for the newer camera at ISO400. At ISO 800 & 1600, the 1100D looks to pull ahead by about half a stop. The question is whether this is improved sensor performance, or are Canon doing noise reduction on the RAW data? I'm not sure it's easy to tell from the colour chart, but there may be a clue in the fabric comparisons. The 450D shows very little moire, whereas the 1100D shows bucket loads of it; this suggests that the 1100D has a weaker AA filter, but why? Surely an entry level buyer of a 12MP camera would be more likely to see moire when using a kit lens than notice any increase in resolution (to be fair, noticing either would probably require viewing the image at 100%). Perhaps Canon have saved costs by using their standard AA filter tuned to the 18MP sensors, but then why use the 12MP sensor at all? The other explantion might be that Canon have fitted a weaker AA filter to cover for lost detail caused by RAW data noise reduction.
I'm no expert here, but I know that a lot of other people on this forum seem to have a good grasp of the technicalities: any ideas...?