The T4i's noise profile is pretty good, though like many cameras it fares a lot better in focused areas than out-of-focus ones. Here, it preserves clean detail until about ISO 400, at which point it starts to degrade.
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Color settings differences aside -- and this is one case where I like the deeper tones produced by the default
Auto Picture Style -- you can do better processing the raws at ISO 800 (bottom) than with the JPEGs (top).