Read about the Camera ISO noise tests in the help section to learn more about the tests and how they are conducted. A key take-away from that page is that noise reduction is completely off unless otherwise specified.
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The difference in high ISO noise between the T3 and the XSi is big - and may answer my question about why Canon did not use the XSi sensor in the T3. Choosing a new sensor looks like a good decision on Canon's part.
The T3 image quality, from a noise perspective, stands up very strongly to all of the other EOS DSLRs exampled here, including the most-recently-released T3i. The T3i and 60D have noticeable resolution advantages over the T3. I would definitely prefer the 5D Mark II's image quality, but the 5D II is in a different price league.
The T3 does not have ISO 12800 available as many of the higher grade models, but I rarely find myself using ISO 12800 anyway. I don't miss it in the T3.
Comparing the image quality between cameras without noise reduction enabled shows what the cameras are capable of without the help of software algorithms. Newer DSLRs have better in-camera noise reduction routines, but I continue to keep it turned off in my cameras. I sometimes enable noise reduction during post processing, but I tend to go light on the reduction settings - due to the loss of detail that accompanies it. The bottom example above demonstrates noise reduction with NR amounts ranging from 1,2 (Luminance,Chrominance) at ISO 100 up to 7,14 at ISO 6400.
Fine details better-hide high ISO noise - and highlight resolution differences. Following is another example that includes such fine details. Note that the T3 examples with noise reduction lose nearly all thread detail at ISO 3200.
Back to the Canon EOS Rebel T3 / 1100D Review.
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